ETH Price: $1,905.33 (-0.92%)

Transaction Decoder

Block:
12931766 at Jul-31-2021 06:32:08 AM +UTC
Transaction Fee:
0.00579117 ETH $11.03
Gas Used:
263,235 Gas / 22 Gwei

Emitted Events:

113 BoneToken.Transfer( from=0x0000000000000000000000000000000000000000, to=DevBoneDistributor, value=179767741935483870967 )
114 BoneToken.Transfer( from=0x0000000000000000000000000000000000000000, to=tBoneBoneDistributor, value=17976774193548387096 )
115 BoneToken.Transfer( from=0x0000000000000000000000000000000000000000, to=xShibBoneDistributor, value=53930322580645161290 )
116 BoneToken.Transfer( from=0x0000000000000000000000000000000000000000, to=xLeashBoneDistributor, value=17976774193548387096 )
117 BoneToken.Transfer( from=0x0000000000000000000000000000000000000000, to=[Receiver] TopDog, value=1797677419354838709677 )
118 BoneToken.Transfer( from=[Receiver] TopDog, to=[Sender] 0x20a8f73318334264f45713362d3133d1d170e767, value=5542953126263069425796 )
119 BoneToken.Transfer( from=[Receiver] TopDog, to=BoneLocker, value=11253874529079565197831 )
120 UniswapV2Pair.Transfer( from=[Receiver] TopDog, to=[Sender] 0x20a8f73318334264f45713362d3133d1d170e767, value=144253127780807150 )
121 TopDog.Withdraw( user=[Sender] 0x20a8f73318334264f45713362d3133d1d170e767, pid=3, amount=144253127780807150 )

Account State Difference:

  Address   Before After State Difference Code
(Hiveon Pool)
5,178.117744244888158943 Eth5,178.123535414888158943 Eth0.00579117
0x20A8F733...1d170e767
64.727233131224016491 Eth
Nonce: 150
64.721441961224016491 Eth
Nonce: 151
0.00579117
0x20E95253...41ee70201
0x94235659...Dbb17C8d7
(Shiba Inu: Migrator)
0x9813037e...6778218d9
0xa404F66B...B239bcdc7
(ShibaSwap: Bone Locker)

Execution Trace

TopDog.withdraw( _pid=3, _amount=144253127780807150 )
  • UniswapV2Pair.balanceOf( 0x94235659cF8b805B2c658f9ea2D6d6DDbb17C8d7 ) => ( 275894712149490312 )
  • BoneToken.mint( _to=0x44c652d679D99BB406167dE9651d2535850FB479, _amount=179767741935483870967 )
  • BoneToken.mint( _to=0x34AD2D8a212cb7d6909D9B523bb5847Aa236CB25, _amount=17976774193548387096 )
  • BoneToken.mint( _to=0x526684cde5E9ed50703469E1e21e388aD084e0f8, _amount=53930322580645161290 )
  • BoneToken.mint( _to=0x68d494e06f70D1DD13f9fAaCd122799D4044412b, _amount=17976774193548387096 )
  • BoneToken.mint( _to=0x94235659cF8b805B2c658f9ea2D6d6DDbb17C8d7, _amount=1797677419354838709677 )
  • BoneToken.balanceOf( account=0x94235659cF8b805B2c658f9ea2D6d6DDbb17C8d7 ) => ( 3816840474038733689529117 )
  • BoneToken.transfer( recipient=0x20A8F73318334264f45713362D3133D1d170e767, amount=5542953126263069425796 ) => ( True )
  • BoneToken.balanceOf( account=0x94235659cF8b805B2c658f9ea2D6d6DDbb17C8d7 ) => ( 3811297520912470620103321 )
  • BoneToken.transfer( recipient=0xa404F66B9278c4aB8428225014266B4B239bcdc7, amount=11253874529079565197831 ) => ( True )
  • BoneLocker.lock( _holder=0x20A8F73318334264f45713362D3133D1d170e767, _amount=11253874529079565197831, _isDev=False )
  • UniswapV2Pair.transfer( to=0x20A8F73318334264f45713362D3133D1d170e767, value=144253127780807150 ) => ( True )
    File 1 of 8: TopDog
    // SPDX-License-Identifier: MIT
    pragma solidity 0.6.12;
    import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
    import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
    import "@openzeppelin/contracts/utils/EnumerableSet.sol";
    import "@openzeppelin/contracts/math/SafeMath.sol";
    import "@openzeppelin/contracts/access/Ownable.sol";
    import "@openzeppelin/contracts/utils/ReentrancyGuard.sol";
    import "./BoneToken.sol";
    import "./BoneLocker.sol";
    interface IMigratorShib {
        // Perform LP token migration from legacy UniswapV2 to ShibaSwap.
        // Take the current LP token address and return the new LP token address.
        // Migrator should have full access to the caller's LP token.
        // Return the new LP token address.
        //
        // XXX Migrator must have allowance access to UniswapV2 LP tokens.
        // ShibaSwap must mint EXACTLY the same amount of ShibaSwap LP tokens or
        // else something bad will happen. Traditional UniswapV2 does not
        // do that so be careful!
        function migrate(IERC20 token) external returns (IERC20);
    }
    // TopDog is the master of Bone. He can make Bone and he is a fair guy.
    //
    // Note that it's ownable and the owner wields tremendous power. The ownership
    // will be transferred to a governance smart contract once BONE is sufficiently
    // distributed and the community can show to govern itself.
    //
    // Have fun reading it. Hopefully it's bug-free. God bless.
    contract TopDog is Ownable, ReentrancyGuard {
        using SafeMath for uint256;
        using SafeERC20 for IERC20;
        // Info of each user.
        struct UserInfo {
            uint256 amount;     // How many LP tokens the user has provided.
            uint256 rewardDebt; // Reward debt. See explanation below.
            //
            // We do some fancy math here. Basically, any point in time, the amount of BONEs
            // entitled to a user but is pending to be distributed is:
            //
            //   pending reward = (user.amount * pool.accBonePerShare) - user.rewardDebt
            //
            // Whenever a user deposits or withdraws LP tokens to a pool. Here's what happens:
            //   1. The pool's `accBonePerShare` (and `lastRewardBlock`) gets updated.
            //   2. User receives the pending reward sent to his/her address.
            //   3. User's `amount` gets updated.
            //   4. User's `rewardDebt` gets updated.
        }
        // Info of each pool.
        struct PoolInfo {
            IERC20 lpToken;           // Address of LP token contract.
            uint256 allocPoint;       // How many allocation points assigned to this pool. BONEs to distribute per block.
            uint256 lastRewardBlock;  // Last block number that BONEs distribution occurs.
            uint256 accBonePerShare; // Accumulated BONEs per share, times 1e12. See below.
        }
        // The BONE TOKEN!
        BoneToken public bone;
        // The Bone Token Locker contract
        BoneLocker public boneLocker;
        // Dev address.
        address public devBoneDistributor;
        address public tBoneBoneDistributor;
        address public xShibBoneDistributor;
        address public xLeashBoneDistributor;
        uint256 public devPercent;
        uint256 public tBonePercent;
        uint256 public xShibPercent;
        uint256 public xLeashPercent;
        // Block number when bonus BONE period ends.
        uint256 public bonusEndBlock;
        // BONE tokens created per block.
        uint256 public bonePerBlock;
        // Bonus muliplier for early bone makers.
        uint256 public constant BONUS_MULTIPLIER = 10;
        // The migrator contract. It has a lot of power. Can only be set through governance (owner).
        IMigratorShib public migrator;
        // Info of each pool.
        PoolInfo[] public poolInfo;
        // Info of each user that stakes LP tokens.
        mapping (uint256 => mapping (address => UserInfo)) public userInfo;
        // Total allocation points. Must be the sum of all allocation points in all pools.
        uint256 public totalAllocPoint = 0;
        // The block number when BONE mining starts.
        uint256 public startBlock;
        // reward percentage to be sent to user directly
        uint256 public rewardMintPercent;
        // devReward percentage to be sent to user directly
        uint256 public devRewardMintPercent;
        event Deposit(address indexed user, uint256 indexed pid, uint256 amount);
        event Withdraw(address indexed user, uint256 indexed pid, uint256 amount);
        event EmergencyWithdraw(address indexed user, uint256 indexed pid, uint256 amount);
        event RewardPerBlock(address indexed user, uint _newReward);
        event SetAddress(string indexed which, address indexed user, address newAddr);
        event SetPercent(string indexed which, address indexed user, uint256 newPercent);
        constructor(
            BoneToken _bone,
            BoneLocker _boneLocker,
            address _devBoneDistributor,
            address _tBoneBoneDistributor,
            address _xShibBoneDistributor,
            address _xLeashBoneDistributor,
            uint256 _bonePerBlock,
            uint256 _startBlock,
            uint256 _bonusEndBlock,
            uint256 _rewardMintPercent,
            uint256 _devRewardMintPercent
        ) public {
            require(address(_bone) != address(0), "_bone is a zero address");
            require(address(_boneLocker) != address(0), "_boneLocker is a zero address");
            bone = _bone;
            boneLocker = _boneLocker;
            devBoneDistributor = _devBoneDistributor;
            bonePerBlock = _bonePerBlock;
            bonusEndBlock = _bonusEndBlock;
            startBlock = _startBlock;
            tBoneBoneDistributor = _tBoneBoneDistributor;
            xShibBoneDistributor = _xShibBoneDistributor;
            xLeashBoneDistributor = _xLeashBoneDistributor;
            rewardMintPercent = _rewardMintPercent;
            devRewardMintPercent = _devRewardMintPercent;
            devPercent = 10;
            tBonePercent = 1;
            xShibPercent = 3;
            xLeashPercent = 1;
        }
        function poolLength() external view returns (uint256) {
            return poolInfo.length;
        }
        mapping(IERC20 => bool) public poolExistence;
        modifier nonDuplicated(IERC20 _lpToken) {
            require(poolExistence[_lpToken] == false, "nonDuplicated: duplicated lpToken");
            _;
        }
        // Add a new lp to the pool. Can only be called by the owner.
        // XXX DO NOT add the same LP token more than once. Rewards will be messed up if you do.
        function add(uint256 _allocPoint, IERC20 _lpToken, bool _withUpdate) public onlyOwner nonDuplicated(_lpToken) {
            if (_withUpdate) {
                massUpdatePools();
            }
            uint256 lastRewardBlock = block.number > startBlock ? block.number : startBlock;
            totalAllocPoint = totalAllocPoint.add(_allocPoint);
            poolExistence[_lpToken] = true;
            poolInfo.push(PoolInfo({
                lpToken: _lpToken,
                allocPoint: _allocPoint,
                lastRewardBlock: lastRewardBlock,
                accBonePerShare: 0
            }));
        }
        // update Reward Rate
        function updateRewardPerBlock(uint256 _perBlock) public onlyOwner {
            massUpdatePools();
            bonePerBlock = _perBlock;
            emit RewardPerBlock(msg.sender, _perBlock);
        }
        // Update the given pool's BONE allocation point. Can only be called by the owner.
        function set(uint256 _pid, uint256 _allocPoint, bool _withUpdate) public onlyOwner {
            if (_withUpdate) {
                massUpdatePools();
            }
            totalAllocPoint = totalAllocPoint.sub(poolInfo[_pid].allocPoint).add(_allocPoint);
            poolInfo[_pid].allocPoint = _allocPoint;
        }
        // Set the migrator contract. Can only be called by the owner.
        function setMigrator(IMigratorShib _migrator) public onlyOwner {
            migrator = _migrator;
            emit SetAddress("Migrator", msg.sender, address(_migrator));
        }
        // Migrate lp token to another lp contract. Can be called by anyone. We trust that migrator contract is good.
        function migrate(uint256 _pid) public {
            require(address(migrator) != address(0), "migrate: no migrator");
            PoolInfo storage pool = poolInfo[_pid];
            IERC20 lpToken = pool.lpToken;
            uint256 bal = lpToken.balanceOf(address(this));
            lpToken.safeApprove(address(migrator), bal);
            IERC20 newLpToken = migrator.migrate(lpToken);
            require(bal == newLpToken.balanceOf(address(this)), "migrate: bad");
            pool.lpToken = newLpToken;
        }
        // Return reward multiplier over the given _from to _to block.
        function getMultiplier(uint256 _from, uint256 _to) public view returns (uint256) {
            if (_from < startBlock) {
                _from = startBlock;
            }
            if (_to <= bonusEndBlock) {
                return _to.sub(_from).mul(BONUS_MULTIPLIER);
            } else if (_from >= bonusEndBlock) {
                return _to.sub(_from);
            } else {
                return bonusEndBlock.sub(_from).mul(BONUS_MULTIPLIER).add(
                    _to.sub(bonusEndBlock)
                );
            }
        }
        // View function to see pending BONEs on frontend.
        function pendingBone(uint256 _pid, address _user) external view returns (uint256) {
            PoolInfo storage pool = poolInfo[_pid];
            UserInfo storage user = userInfo[_pid][_user];
            uint256 accBonePerShare = pool.accBonePerShare;
            uint256 lpSupply = pool.lpToken.balanceOf(address(this));
            if (block.number > pool.lastRewardBlock && lpSupply != 0) {
                uint256 multiplier = getMultiplier(pool.lastRewardBlock, block.number);
                uint256 boneReward = multiplier.mul(bonePerBlock).mul(pool.allocPoint).div(totalAllocPoint);
                accBonePerShare = accBonePerShare.add(boneReward.mul(1e12).div(lpSupply));
            }
            return user.amount.mul(accBonePerShare).div(1e12).sub(user.rewardDebt);
        }
        // Update reward variables for all pools. Be careful of gas spending!
        function massUpdatePools() public {
            uint256 length = poolInfo.length;
            for (uint256 pid = 0; pid < length; ++pid) {
                updatePool(pid);
            }
        }
        // Update reward variables of the given pool to be up-to-date.
        function updatePool(uint256 _pid) public {
            PoolInfo storage pool = poolInfo[_pid];
            if (block.number <= pool.lastRewardBlock) {
                return;
            }
            uint256 lpSupply = pool.lpToken.balanceOf(address(this));
            if (lpSupply == 0) {
                pool.lastRewardBlock = block.number;
                return;
            }
            uint256 multiplier = getMultiplier(pool.lastRewardBlock, block.number);
            uint256 boneReward = multiplier.mul(bonePerBlock).mul(pool.allocPoint).div(totalAllocPoint);
            uint256 devBoneReward = boneReward.mul(devPercent).div(100); // devPercent rewards to dev address
            bone.mint(devBoneDistributor, devBoneReward.mul(devRewardMintPercent).div(100)); // partial devPercent rewards to dev address
            if(devRewardMintPercent != 100) {
                bone.mint(address(boneLocker), devBoneReward.sub(devBoneReward.mul(devRewardMintPercent).div(100))); // rest devPercent rewards locked to bone token contract
                boneLocker.lock(devBoneDistributor, devBoneReward.sub(devBoneReward.mul(devRewardMintPercent).div(100)), true);
            }
            bone.mint(tBoneBoneDistributor, boneReward.mul(tBonePercent).div(100)); // tBonePercent rewards to tBoneBoneDistributor address
            bone.mint(xShibBoneDistributor, boneReward.mul(xShibPercent).div(100)); // xShibPercent rewards to xShibBoneDistributor address
            bone.mint(xLeashBoneDistributor, boneReward.mul(xLeashPercent).div(100)); // xLeashPercent rewards to xLeashBoneDistributor address
            bone.mint(address(this), boneReward);
            pool.accBonePerShare = pool.accBonePerShare.add(boneReward.mul(1e12).div(lpSupply));
            pool.lastRewardBlock = block.number;
        }
        // Deposit LP tokens to TopDog for BONE allocation.
        function deposit(uint256 _pid, uint256 _amount) public nonReentrant {
            PoolInfo storage pool = poolInfo[_pid];
            UserInfo storage user = userInfo[_pid][msg.sender];
            updatePool(_pid);
            if (user.amount > 0) {
                uint256 pending = user.amount.mul(pool.accBonePerShare).div(1e12).sub(user.rewardDebt);
                if(pending > 0) {
                    // safeBoneTransfer(msg.sender, pending);
                    uint256 sendAmount = pending.mul(rewardMintPercent).div(100);
                    safeBoneTransfer(msg.sender, sendAmount);
                    if(rewardMintPercent != 100) {
                        safeBoneTransfer(address(boneLocker), pending.sub(sendAmount)); // Rest amount sent to Bone token contract
                        boneLocker.lock(msg.sender, pending.sub(sendAmount), false); //function called for token time-lock
                    }
                }
            }
            if(_amount > 0) {
                pool.lpToken.safeTransferFrom(address(msg.sender), address(this), _amount);
                user.amount = user.amount.add(_amount);
            }
            user.rewardDebt = user.amount.mul(pool.accBonePerShare).div(1e12);
            emit Deposit(msg.sender, _pid, _amount);
        }
        // Withdraw LP tokens from TopDog.
        function withdraw(uint256 _pid, uint256 _amount) public nonReentrant {
            PoolInfo storage pool = poolInfo[_pid];
            UserInfo storage user = userInfo[_pid][msg.sender];
            require(user.amount >= _amount, "withdraw: not good");
            updatePool(_pid);
            uint256 pending = user.amount.mul(pool.accBonePerShare).div(1e12).sub(user.rewardDebt);
            if(pending > 0) {
                    uint256 sendAmount = pending.mul(rewardMintPercent).div(100);
                    safeBoneTransfer(msg.sender, sendAmount);
                    if(rewardMintPercent != 100) {
                        safeBoneTransfer(address(boneLocker), pending.sub(sendAmount)); // Rest amount sent to Bone token contract
                        boneLocker.lock(msg.sender, pending.sub(sendAmount), false); //function called for token time-lock
                    }
            }
            if(_amount > 0) {
                user.amount = user.amount.sub(_amount);
                pool.lpToken.safeTransfer(address(msg.sender), _amount);
            }
            user.rewardDebt = user.amount.mul(pool.accBonePerShare).div(1e12);
            emit Withdraw(msg.sender, _pid, _amount);
        }
        // Withdraw without caring about rewards. EMERGENCY ONLY.
        function emergencyWithdraw(uint256 _pid) public {
            PoolInfo storage pool = poolInfo[_pid];
            UserInfo storage user = userInfo[_pid][msg.sender];
            uint256 amount = user.amount;
            user.amount = 0;
            user.rewardDebt = 0;
            pool.lpToken.safeTransfer(address(msg.sender), amount);
            emit EmergencyWithdraw(msg.sender, _pid, amount);
        }
        // Safe bone transfer function, just in case if rounding error causes pool to not have enough BONEs.
        function safeBoneTransfer(address _to, uint256 _amount) internal {
            uint256 boneBal = bone.balanceOf(address(this));
            if (_amount > boneBal) {
                bone.transfer(_to, boneBal);
            } else {
                bone.transfer(_to, _amount);
            }
        }
        // Update boneLocker address by the owner.
        function boneLockerUpdate(address _boneLocker) public onlyOwner {
            boneLocker = BoneLocker(_boneLocker);
        }
        // Update dev bone distributor address by the owner.
        function devBoneDistributorUpdate(address _devBoneDistributor) public onlyOwner {
            devBoneDistributor = _devBoneDistributor;
        }
        // Update rewardMintPercent value, currently set to 33%, called by the owner
        function setRewardMintPercent(uint256 _newPercent) public onlyOwner{
            rewardMintPercent = _newPercent;
            emit SetPercent("RewardMint", msg.sender, _newPercent);
        }
        // Update devRewardMintPercent value, currently set to 50%, called by the owner
        function setDevRewardMintPercent(uint256 _newPercent) public onlyOwner{
            devRewardMintPercent = _newPercent;
            emit SetPercent("DevRewardMint", msg.sender, _newPercent);
        }
        // Update locking period for users and dev
        function setLockingPeriod(uint256 _newLockingPeriod, uint256 _newDevLockingPeriod) public onlyOwner{
            boneLocker.setLockingPeriod(_newLockingPeriod, _newDevLockingPeriod);
        }
        // Call emergency withdraw to transfer bone tokens to any other address, onlyOwner function
        function callEmergencyWithdraw(address _to) public onlyOwner{
            boneLocker.emergencyWithdrawOwner(_to);
        }
        // Update tBoneBoneDistributor address by the owner.
        function tBoneBoneDistributorUpdate(address _tBoneBoneDistributor) public onlyOwner {
            tBoneBoneDistributor = _tBoneBoneDistributor;
            emit SetAddress("tBone-BoneDistributor", msg.sender, _tBoneBoneDistributor);
        }
        // Update xShibBoneDistributor address by the owner.
        function xShibBoneDistributorUpdate(address _xShibBoneDistributor) public onlyOwner {
            xShibBoneDistributor = _xShibBoneDistributor;
            emit SetAddress("xShib-BoneDistributor", msg.sender, _xShibBoneDistributor);
        }
        // Update xLeashBoneDistributor address by the owner.
        function xLeashBoneDistributorUpdate(address _xLeashBoneDistributor) public onlyOwner {
            xLeashBoneDistributor = _xLeashBoneDistributor;
            emit SetAddress("xLeash-BoneDistributor", msg.sender, _xLeashBoneDistributor);
        }
        // Update devPercent by the owner.
        function devPercentUpdate(uint _devPercent) public onlyOwner {
            require(_devPercent <= 10, "topDog: Percent too high");
            devPercent = _devPercent;
            emit SetPercent("Dev share", msg.sender, _devPercent);
        }
        // Update tBonePercent by the owner.
        function tBonePercentUpdate(uint _tBonePercent) public onlyOwner {
            tBonePercent = _tBonePercent;
            emit SetPercent("tBone share", msg.sender, _tBonePercent);
        }
        // Update xShibPercent by the owner.
        function xShibPercentUpdate(uint _xShibPercent) public onlyOwner {
            xShibPercent = _xShibPercent;
            emit SetPercent("xShib share", msg.sender, _xShibPercent);
        }
        // Update xLeashPercent by the owner.
        function xLeashPercentUpdate(uint _xLeashPercent) public onlyOwner {
            xLeashPercent = _xLeashPercent;
            emit SetPercent("xLeash share", msg.sender, _xLeashPercent);
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    /**
     * @dev Interface of the ERC20 standard as defined in the EIP.
     */
    interface IERC20 {
        /**
         * @dev Returns the amount of tokens in existence.
         */
        function totalSupply() external view returns (uint256);
        /**
         * @dev Returns the amount of tokens owned by `account`.
         */
        function balanceOf(address account) external view returns (uint256);
        /**
         * @dev Moves `amount` tokens from the caller's account to `recipient`.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transfer(address recipient, uint256 amount) external returns (bool);
        /**
         * @dev Returns the remaining number of tokens that `spender` will be
         * allowed to spend on behalf of `owner` through {transferFrom}. This is
         * zero by default.
         *
         * This value changes when {approve} or {transferFrom} are called.
         */
        function allowance(address owner, address spender) external view returns (uint256);
        /**
         * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * IMPORTANT: Beware that changing an allowance with this method brings the risk
         * that someone may use both the old and the new allowance by unfortunate
         * transaction ordering. One possible solution to mitigate this race
         * condition is to first reduce the spender's allowance to 0 and set the
         * desired value afterwards:
         * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
         *
         * Emits an {Approval} event.
         */
        function approve(address spender, uint256 amount) external returns (bool);
        /**
         * @dev Moves `amount` tokens from `sender` to `recipient` using the
         * allowance mechanism. `amount` is then deducted from the caller's
         * allowance.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
        /**
         * @dev Emitted when `value` tokens are moved from one account (`from`) to
         * another (`to`).
         *
         * Note that `value` may be zero.
         */
        event Transfer(address indexed from, address indexed to, uint256 value);
        /**
         * @dev Emitted when the allowance of a `spender` for an `owner` is set by
         * a call to {approve}. `value` is the new allowance.
         */
        event Approval(address indexed owner, address indexed spender, uint256 value);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    import "./IERC20.sol";
    import "../../math/SafeMath.sol";
    import "../../utils/Address.sol";
    /**
     * @title SafeERC20
     * @dev Wrappers around ERC20 operations that throw on failure (when the token
     * contract returns false). Tokens that return no value (and instead revert or
     * throw on failure) are also supported, non-reverting calls are assumed to be
     * successful.
     * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
     * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
     */
    library SafeERC20 {
        using SafeMath for uint256;
        using Address for address;
        function safeTransfer(IERC20 token, address to, uint256 value) internal {
            _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
        }
        function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
            _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
        }
        /**
         * @dev Deprecated. This function has issues similar to the ones found in
         * {IERC20-approve}, and its usage is discouraged.
         *
         * Whenever possible, use {safeIncreaseAllowance} and
         * {safeDecreaseAllowance} instead.
         */
        function safeApprove(IERC20 token, address spender, uint256 value) internal {
            // safeApprove should only be called when setting an initial allowance,
            // or when resetting it to zero. To increase and decrease it, use
            // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
            // solhint-disable-next-line max-line-length
            require((value == 0) || (token.allowance(address(this), spender) == 0),
                "SafeERC20: approve from non-zero to non-zero allowance"
            );
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
        }
        function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
            uint256 newAllowance = token.allowance(address(this), spender).add(value);
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
        }
        function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
            uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero");
            _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
        }
        /**
         * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
         * on the return value: the return value is optional (but if data is returned, it must not be false).
         * @param token The token targeted by the call.
         * @param data The call data (encoded using abi.encode or one of its variants).
         */
        function _callOptionalReturn(IERC20 token, bytes memory data) private {
            // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
            // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
            // the target address contains contract code and also asserts for success in the low-level call.
            bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
            if (returndata.length > 0) { // Return data is optional
                // solhint-disable-next-line max-line-length
                require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
            }
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    /**
     * @dev Library for managing
     * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
     * types.
     *
     * Sets have the following properties:
     *
     * - Elements are added, removed, and checked for existence in constant time
     * (O(1)).
     * - Elements are enumerated in O(n). No guarantees are made on the ordering.
     *
     * ```
     * contract Example {
     *     // Add the library methods
     *     using EnumerableSet for EnumerableSet.AddressSet;
     *
     *     // Declare a set state variable
     *     EnumerableSet.AddressSet private mySet;
     * }
     * ```
     *
     * As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`)
     * and `uint256` (`UintSet`) are supported.
     */
    library EnumerableSet {
        // To implement this library for multiple types with as little code
        // repetition as possible, we write it in terms of a generic Set type with
        // bytes32 values.
        // The Set implementation uses private functions, and user-facing
        // implementations (such as AddressSet) are just wrappers around the
        // underlying Set.
        // This means that we can only create new EnumerableSets for types that fit
        // in bytes32.
        struct Set {
            // Storage of set values
            bytes32[] _values;
            // Position of the value in the `values` array, plus 1 because index 0
            // means a value is not in the set.
            mapping (bytes32 => uint256) _indexes;
        }
        /**
         * @dev Add a value to a set. O(1).
         *
         * Returns true if the value was added to the set, that is if it was not
         * already present.
         */
        function _add(Set storage set, bytes32 value) private returns (bool) {
            if (!_contains(set, value)) {
                set._values.push(value);
                // The value is stored at length-1, but we add 1 to all indexes
                // and use 0 as a sentinel value
                set._indexes[value] = set._values.length;
                return true;
            } else {
                return false;
            }
        }
        /**
         * @dev Removes a value from a set. O(1).
         *
         * Returns true if the value was removed from the set, that is if it was
         * present.
         */
        function _remove(Set storage set, bytes32 value) private returns (bool) {
            // We read and store the value's index to prevent multiple reads from the same storage slot
            uint256 valueIndex = set._indexes[value];
            if (valueIndex != 0) { // Equivalent to contains(set, value)
                // To delete an element from the _values array in O(1), we swap the element to delete with the last one in
                // the array, and then remove the last element (sometimes called as 'swap and pop').
                // This modifies the order of the array, as noted in {at}.
                uint256 toDeleteIndex = valueIndex - 1;
                uint256 lastIndex = set._values.length - 1;
                // When the value to delete is the last one, the swap operation is unnecessary. However, since this occurs
                // so rarely, we still do the swap anyway to avoid the gas cost of adding an 'if' statement.
                bytes32 lastvalue = set._values[lastIndex];
                // Move the last value to the index where the value to delete is
                set._values[toDeleteIndex] = lastvalue;
                // Update the index for the moved value
                set._indexes[lastvalue] = toDeleteIndex + 1; // All indexes are 1-based
                // Delete the slot where the moved value was stored
                set._values.pop();
                // Delete the index for the deleted slot
                delete set._indexes[value];
                return true;
            } else {
                return false;
            }
        }
        /**
         * @dev Returns true if the value is in the set. O(1).
         */
        function _contains(Set storage set, bytes32 value) private view returns (bool) {
            return set._indexes[value] != 0;
        }
        /**
         * @dev Returns the number of values on the set. O(1).
         */
        function _length(Set storage set) private view returns (uint256) {
            return set._values.length;
        }
       /**
        * @dev Returns the value stored at position `index` in the set. O(1).
        *
        * Note that there are no guarantees on the ordering of values inside the
        * array, and it may change when more values are added or removed.
        *
        * Requirements:
        *
        * - `index` must be strictly less than {length}.
        */
        function _at(Set storage set, uint256 index) private view returns (bytes32) {
            require(set._values.length > index, "EnumerableSet: index out of bounds");
            return set._values[index];
        }
        // Bytes32Set
        struct Bytes32Set {
            Set _inner;
        }
        /**
         * @dev Add a value to a set. O(1).
         *
         * Returns true if the value was added to the set, that is if it was not
         * already present.
         */
        function add(Bytes32Set storage set, bytes32 value) internal returns (bool) {
            return _add(set._inner, value);
        }
        /**
         * @dev Removes a value from a set. O(1).
         *
         * Returns true if the value was removed from the set, that is if it was
         * present.
         */
        function remove(Bytes32Set storage set, bytes32 value) internal returns (bool) {
            return _remove(set._inner, value);
        }
        /**
         * @dev Returns true if the value is in the set. O(1).
         */
        function contains(Bytes32Set storage set, bytes32 value) internal view returns (bool) {
            return _contains(set._inner, value);
        }
        /**
         * @dev Returns the number of values in the set. O(1).
         */
        function length(Bytes32Set storage set) internal view returns (uint256) {
            return _length(set._inner);
        }
       /**
        * @dev Returns the value stored at position `index` in the set. O(1).
        *
        * Note that there are no guarantees on the ordering of values inside the
        * array, and it may change when more values are added or removed.
        *
        * Requirements:
        *
        * - `index` must be strictly less than {length}.
        */
        function at(Bytes32Set storage set, uint256 index) internal view returns (bytes32) {
            return _at(set._inner, index);
        }
        // AddressSet
        struct AddressSet {
            Set _inner;
        }
        /**
         * @dev Add a value to a set. O(1).
         *
         * Returns true if the value was added to the set, that is if it was not
         * already present.
         */
        function add(AddressSet storage set, address value) internal returns (bool) {
            return _add(set._inner, bytes32(uint256(uint160(value))));
        }
        /**
         * @dev Removes a value from a set. O(1).
         *
         * Returns true if the value was removed from the set, that is if it was
         * present.
         */
        function remove(AddressSet storage set, address value) internal returns (bool) {
            return _remove(set._inner, bytes32(uint256(uint160(value))));
        }
        /**
         * @dev Returns true if the value is in the set. O(1).
         */
        function contains(AddressSet storage set, address value) internal view returns (bool) {
            return _contains(set._inner, bytes32(uint256(uint160(value))));
        }
        /**
         * @dev Returns the number of values in the set. O(1).
         */
        function length(AddressSet storage set) internal view returns (uint256) {
            return _length(set._inner);
        }
       /**
        * @dev Returns the value stored at position `index` in the set. O(1).
        *
        * Note that there are no guarantees on the ordering of values inside the
        * array, and it may change when more values are added or removed.
        *
        * Requirements:
        *
        * - `index` must be strictly less than {length}.
        */
        function at(AddressSet storage set, uint256 index) internal view returns (address) {
            return address(uint160(uint256(_at(set._inner, index))));
        }
        // UintSet
        struct UintSet {
            Set _inner;
        }
        /**
         * @dev Add a value to a set. O(1).
         *
         * Returns true if the value was added to the set, that is if it was not
         * already present.
         */
        function add(UintSet storage set, uint256 value) internal returns (bool) {
            return _add(set._inner, bytes32(value));
        }
        /**
         * @dev Removes a value from a set. O(1).
         *
         * Returns true if the value was removed from the set, that is if it was
         * present.
         */
        function remove(UintSet storage set, uint256 value) internal returns (bool) {
            return _remove(set._inner, bytes32(value));
        }
        /**
         * @dev Returns true if the value is in the set. O(1).
         */
        function contains(UintSet storage set, uint256 value) internal view returns (bool) {
            return _contains(set._inner, bytes32(value));
        }
        /**
         * @dev Returns the number of values on the set. O(1).
         */
        function length(UintSet storage set) internal view returns (uint256) {
            return _length(set._inner);
        }
       /**
        * @dev Returns the value stored at position `index` in the set. O(1).
        *
        * Note that there are no guarantees on the ordering of values inside the
        * array, and it may change when more values are added or removed.
        *
        * Requirements:
        *
        * - `index` must be strictly less than {length}.
        */
        function at(UintSet storage set, uint256 index) internal view returns (uint256) {
            return uint256(_at(set._inner, index));
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    /**
     * @dev Wrappers over Solidity's arithmetic operations with added overflow
     * checks.
     *
     * Arithmetic operations in Solidity wrap on overflow. This can easily result
     * in bugs, because programmers usually assume that an overflow raises an
     * error, which is the standard behavior in high level programming languages.
     * `SafeMath` restores this intuition by reverting the transaction when an
     * operation overflows.
     *
     * Using this library instead of the unchecked operations eliminates an entire
     * class of bugs, so it's recommended to use it always.
     */
    library SafeMath {
        /**
         * @dev Returns the addition of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
        /**
         * @dev Returns the substraction of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
        /**
         * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
            // benefit is lost if 'b' is also tested.
            // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
            if (a == 0) return (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
        /**
         * @dev Returns the division of two unsigned integers, with a division by zero flag.
         *
         * _Available since v3.4._
         */
        function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
         *
         * _Available since v3.4._
         */
        function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
        /**
         * @dev Returns the addition of two unsigned integers, reverting on
         * overflow.
         *
         * Counterpart to Solidity's `+` operator.
         *
         * Requirements:
         *
         * - Addition cannot overflow.
         */
        function add(uint256 a, uint256 b) internal pure returns (uint256) {
            uint256 c = a + b;
            require(c >= a, "SafeMath: addition overflow");
            return c;
        }
        /**
         * @dev Returns the subtraction of two unsigned integers, reverting on
         * overflow (when the result is negative).
         *
         * Counterpart to Solidity's `-` operator.
         *
         * Requirements:
         *
         * - Subtraction cannot overflow.
         */
        function sub(uint256 a, uint256 b) internal pure returns (uint256) {
            require(b <= a, "SafeMath: subtraction overflow");
            return a - b;
        }
        /**
         * @dev Returns the multiplication of two unsigned integers, reverting on
         * overflow.
         *
         * Counterpart to Solidity's `*` operator.
         *
         * Requirements:
         *
         * - Multiplication cannot overflow.
         */
        function mul(uint256 a, uint256 b) internal pure returns (uint256) {
            if (a == 0) return 0;
            uint256 c = a * b;
            require(c / a == b, "SafeMath: multiplication overflow");
            return c;
        }
        /**
         * @dev Returns the integer division of two unsigned integers, reverting on
         * division by zero. The result is rounded towards zero.
         *
         * Counterpart to Solidity's `/` operator. Note: this function uses a
         * `revert` opcode (which leaves remaining gas untouched) while Solidity
         * uses an invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function div(uint256 a, uint256 b) internal pure returns (uint256) {
            require(b > 0, "SafeMath: division by zero");
            return a / b;
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
         * reverting when dividing by zero.
         *
         * Counterpart to Solidity's `%` operator. This function uses a `revert`
         * opcode (which leaves remaining gas untouched) while Solidity uses an
         * invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function mod(uint256 a, uint256 b) internal pure returns (uint256) {
            require(b > 0, "SafeMath: modulo by zero");
            return a % b;
        }
        /**
         * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
         * overflow (when the result is negative).
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {trySub}.
         *
         * Counterpart to Solidity's `-` operator.
         *
         * Requirements:
         *
         * - Subtraction cannot overflow.
         */
        function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
            require(b <= a, errorMessage);
            return a - b;
        }
        /**
         * @dev Returns the integer division of two unsigned integers, reverting with custom message on
         * division by zero. The result is rounded towards zero.
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {tryDiv}.
         *
         * Counterpart to Solidity's `/` operator. Note: this function uses a
         * `revert` opcode (which leaves remaining gas untouched) while Solidity
         * uses an invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
            require(b > 0, errorMessage);
            return a / b;
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
         * reverting with custom message when dividing by zero.
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {tryMod}.
         *
         * Counterpart to Solidity's `%` operator. This function uses a `revert`
         * opcode (which leaves remaining gas untouched) while Solidity uses an
         * invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    import "../utils/Context.sol";
    /**
     * @dev Contract module which provides a basic access control mechanism, where
     * there is an account (an owner) that can be granted exclusive access to
     * specific functions.
     *
     * By default, the owner account will be the one that deploys the contract. This
     * can later be changed with {transferOwnership}.
     *
     * This module is used through inheritance. It will make available the modifier
     * `onlyOwner`, which can be applied to your functions to restrict their use to
     * the owner.
     */
    abstract contract Ownable is Context {
        address private _owner;
        event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
        /**
         * @dev Initializes the contract setting the deployer as the initial owner.
         */
        constructor () internal {
            address msgSender = _msgSender();
            _owner = msgSender;
            emit OwnershipTransferred(address(0), msgSender);
        }
        /**
         * @dev Returns the address of the current owner.
         */
        function owner() public view virtual returns (address) {
            return _owner;
        }
        /**
         * @dev Throws if called by any account other than the owner.
         */
        modifier onlyOwner() {
            require(owner() == _msgSender(), "Ownable: caller is not the owner");
            _;
        }
        /**
         * @dev Leaves the contract without owner. It will not be possible to call
         * `onlyOwner` functions anymore. Can only be called by the current owner.
         *
         * NOTE: Renouncing ownership will leave the contract without an owner,
         * thereby removing any functionality that is only available to the owner.
         */
        function renounceOwnership() public virtual onlyOwner {
            emit OwnershipTransferred(_owner, address(0));
            _owner = address(0);
        }
        /**
         * @dev Transfers ownership of the contract to a new account (`newOwner`).
         * Can only be called by the current owner.
         */
        function transferOwnership(address newOwner) public virtual onlyOwner {
            require(newOwner != address(0), "Ownable: new owner is the zero address");
            emit OwnershipTransferred(_owner, newOwner);
            _owner = newOwner;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    /**
     * @dev Contract module that helps prevent reentrant calls to a function.
     *
     * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
     * available, which can be applied to functions to make sure there are no nested
     * (reentrant) calls to them.
     *
     * Note that because there is a single `nonReentrant` guard, functions marked as
     * `nonReentrant` may not call one another. This can be worked around by making
     * those functions `private`, and then adding `external` `nonReentrant` entry
     * points to them.
     *
     * TIP: If you would like to learn more about reentrancy and alternative ways
     * to protect against it, check out our blog post
     * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
     */
    abstract contract ReentrancyGuard {
        // Booleans are more expensive than uint256 or any type that takes up a full
        // word because each write operation emits an extra SLOAD to first read the
        // slot's contents, replace the bits taken up by the boolean, and then write
        // back. This is the compiler's defense against contract upgrades and
        // pointer aliasing, and it cannot be disabled.
        // The values being non-zero value makes deployment a bit more expensive,
        // but in exchange the refund on every call to nonReentrant will be lower in
        // amount. Since refunds are capped to a percentage of the total
        // transaction's gas, it is best to keep them low in cases like this one, to
        // increase the likelihood of the full refund coming into effect.
        uint256 private constant _NOT_ENTERED = 1;
        uint256 private constant _ENTERED = 2;
        uint256 private _status;
        constructor () internal {
            _status = _NOT_ENTERED;
        }
        /**
         * @dev Prevents a contract from calling itself, directly or indirectly.
         * Calling a `nonReentrant` function from another `nonReentrant`
         * function is not supported. It is possible to prevent this from happening
         * by making the `nonReentrant` function external, and make it call a
         * `private` function that does the actual work.
         */
        modifier nonReentrant() {
            // On the first call to nonReentrant, _notEntered will be true
            require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
            // Any calls to nonReentrant after this point will fail
            _status = _ENTERED;
            _;
            // By storing the original value once again, a refund is triggered (see
            // https://eips.ethereum.org/EIPS/eip-2200)
            _status = _NOT_ENTERED;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity 0.6.12;
    import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
    import "@openzeppelin/contracts/access/Ownable.sol";
    // BoneToken with Governance.
    contract BoneToken is ERC20("BONE SHIBASWAP", "BONE"), Ownable {
        /// @notice Creates `_amount` token to `_to`. Must only be called by the owner (TopDog).
        function mint(address _to, uint256 _amount) public onlyOwner {
            _mint(_to, _amount);
            _moveDelegates(address(0), _delegates[_to], _amount);
        }
        function _transfer(address sender, address recipient, uint256 amount) internal override {
            super._transfer(sender, recipient, amount);
            _moveDelegates(_delegates[sender], _delegates[recipient], amount);
        }
        // Copied and modified from YAM code:
        // https://github.com/yam-finance/yam-protocol/blob/master/contracts/token/YAMGovernanceStorage.sol
        // https://github.com/yam-finance/yam-protocol/blob/master/contracts/token/YAMGovernance.sol
        // Which is copied and modified from COMPOUND:
        // https://github.com/compound-finance/compound-protocol/blob/master/contracts/Governance/Comp.sol
        /// @dev A record of each accounts delegate
        mapping (address => address) internal _delegates;
        /// @notice A checkpoint for marking number of votes from a given block
        struct Checkpoint {
            uint32 fromBlock;
            uint256 votes;
        }
        /// @notice A record of votes checkpoints for each account, by index
        mapping (address => mapping (uint32 => Checkpoint)) public checkpoints;
        /// @notice The number of checkpoints for each account
        mapping (address => uint32) public numCheckpoints;
        /// @notice The EIP-712 typehash for the contract's domain
        bytes32 public constant DOMAIN_TYPEHASH = keccak256("EIP712Domain(string name,uint256 chainId,address verifyingContract)");
        /// @notice The EIP-712 typehash for the delegation struct used by the contract
        bytes32 public constant DELEGATION_TYPEHASH = keccak256("Delegation(address delegatee,uint256 nonce,uint256 expiry)");
        /// @notice A record of states for signing / validating signatures
        mapping (address => uint) public nonces;
          /// @notice An event thats emitted when an account changes its delegate
        event DelegateChanged(address indexed delegator, address indexed fromDelegate, address indexed toDelegate);
        /// @notice An event thats emitted when a delegate account's vote balance changes
        event DelegateVotesChanged(address indexed delegate, uint previousBalance, uint newBalance);
        /**
         * @notice Delegate votes from `msg.sender` to `delegatee`
         * @param delegator The address to get delegatee for
         */
        function delegates(address delegator)
            external
            view
            returns (address)
        {
            return _delegates[delegator];
        }
       /**
        * @notice Delegate votes from `msg.sender` to `delegatee`
        * @param delegatee The address to delegate votes to
        */
        function delegate(address delegatee) external {
            return _delegate(msg.sender, delegatee);
        }
        /**
         * @notice Delegates votes from signatory to `delegatee`
         * @param delegatee The address to delegate votes to
         * @param nonce The contract state required to match the signature
         * @param expiry The time at which to expire the signature
         * @param v The recovery byte of the signature
         * @param r Half of the ECDSA signature pair
         * @param s Half of the ECDSA signature pair
         */
        function delegateBySig(
            address delegatee,
            uint nonce,
            uint expiry,
            uint8 v,
            bytes32 r,
            bytes32 s
        )
            external
        {
            bytes32 domainSeparator = keccak256(
                abi.encode(
                    DOMAIN_TYPEHASH,
                    keccak256(bytes(name())),
                    getChainId(),
                    address(this)
                )
            );
            bytes32 structHash = keccak256(
                abi.encode(
                    DELEGATION_TYPEHASH,
                    delegatee,
                    nonce,
                    expiry
                )
            );
            bytes32 digest = keccak256(
                abi.encodePacked(
                    "\\x19\\x01",
                    domainSeparator,
                    structHash
                )
            );
            address signatory = ecrecover(digest, v, r, s);
            require(signatory != address(0), "BONE::delegateBySig: invalid signature");
            require(nonce == nonces[signatory]++, "BONE::delegateBySig: invalid nonce");
            require(now <= expiry, "BONE::delegateBySig: signature expired");
            return _delegate(signatory, delegatee);
        }
        /**
         * @notice Gets the current votes balance for `account`
         * @param account The address to get votes balance
         * @return The number of current votes for `account`
         */
        function getCurrentVotes(address account)
            external
            view
            returns (uint256)
        {
            uint32 nCheckpoints = numCheckpoints[account];
            return nCheckpoints > 0 ? checkpoints[account][nCheckpoints - 1].votes : 0;
        }
        /**
         * @notice Determine the prior number of votes for an account as of a block number
         * @dev Block number must be a finalized block or else this function will revert to prevent misinformation.
         * @param account The address of the account to check
         * @param blockNumber The block number to get the vote balance at
         * @return The number of votes the account had as of the given block
         */
        function getPriorVotes(address account, uint blockNumber)
            external
            view
            returns (uint256)
        {
            require(blockNumber < block.number, "BONE::getPriorVotes: not yet determined");
            uint32 nCheckpoints = numCheckpoints[account];
            if (nCheckpoints == 0) {
                return 0;
            }
            // First check most recent balance
            if (checkpoints[account][nCheckpoints - 1].fromBlock <= blockNumber) {
                return checkpoints[account][nCheckpoints - 1].votes;
            }
            // Next check implicit zero balance
            if (checkpoints[account][0].fromBlock > blockNumber) {
                return 0;
            }
            uint32 lower = 0;
            uint32 upper = nCheckpoints - 1;
            while (upper > lower) {
                uint32 center = upper - (upper - lower) / 2; // ceil, avoiding overflow
                Checkpoint memory cp = checkpoints[account][center];
                if (cp.fromBlock == blockNumber) {
                    return cp.votes;
                } else if (cp.fromBlock < blockNumber) {
                    lower = center;
                } else {
                    upper = center - 1;
                }
            }
            return checkpoints[account][lower].votes;
        }
        function _delegate(address delegator, address delegatee)
            internal
        {
            address currentDelegate = _delegates[delegator];
            uint256 delegatorBalance = balanceOf(delegator); // balance of underlying BONEs (not scaled);
            _delegates[delegator] = delegatee;
            emit DelegateChanged(delegator, currentDelegate, delegatee);
            _moveDelegates(currentDelegate, delegatee, delegatorBalance);
        }
        function _moveDelegates(address srcRep, address dstRep, uint256 amount) internal {
            if (srcRep != dstRep && amount > 0) {
                if (srcRep != address(0)) {
                    // decrease old representative
                    uint32 srcRepNum = numCheckpoints[srcRep];
                    uint256 srcRepOld = srcRepNum > 0 ? checkpoints[srcRep][srcRepNum - 1].votes : 0;
                    uint256 srcRepNew = srcRepOld.sub(amount);
                    _writeCheckpoint(srcRep, srcRepNum, srcRepOld, srcRepNew);
                }
                if (dstRep != address(0)) {
                    // increase new representative
                    uint32 dstRepNum = numCheckpoints[dstRep];
                    uint256 dstRepOld = dstRepNum > 0 ? checkpoints[dstRep][dstRepNum - 1].votes : 0;
                    uint256 dstRepNew = dstRepOld.add(amount);
                    _writeCheckpoint(dstRep, dstRepNum, dstRepOld, dstRepNew);
                }
            }
        }
        function _writeCheckpoint(
            address delegatee,
            uint32 nCheckpoints,
            uint256 oldVotes,
            uint256 newVotes
        )
            internal
        {
            uint32 blockNumber = safe32(block.number, "BONE::_writeCheckpoint: block number exceeds 32 bits");
            if (nCheckpoints > 0 && checkpoints[delegatee][nCheckpoints - 1].fromBlock == blockNumber) {
                checkpoints[delegatee][nCheckpoints - 1].votes = newVotes;
            } else {
                checkpoints[delegatee][nCheckpoints] = Checkpoint(blockNumber, newVotes);
                require(nCheckpoints + 1 > nCheckpoints, "BONE::_writeCheckpoint: new checkpoint exceeds 32 bits");
                numCheckpoints[delegatee] = nCheckpoints + 1;
            }
            emit DelegateVotesChanged(delegatee, oldVotes, newVotes);
        }
        function safe32(uint n, string memory errorMessage) internal pure returns (uint32) {
            require(n < 2**32, errorMessage);
            return uint32(n);
        }
        function getChainId() internal pure returns (uint) {
            uint256 chainId;
            assembly { chainId := chainid() }
            return chainId;
        }
    }// SPDX-License-Identifier: UNLICENSED
    pragma solidity 0.6.12;
    import "@openzeppelin/contracts/access/Ownable.sol";
    import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
    import "@openzeppelin/contracts/math/SafeMath.sol";
    // BoneToken locker contract.
    contract BoneLocker is Ownable {
        using SafeMath for uint256;
        IERC20 boneToken;
        address emergencyAddress;
        bool emergencyFlag = false;
        struct LockInfo{
            uint256 _amount;
            uint256 _timestamp;
            bool _isDev;
        }
        uint256 public lockingPeriod;
        uint256 public devLockingPeriod;
        mapping (address => LockInfo[]) public lockInfoByUser;
        mapping (address => uint256) public latestCounterByUser;
        mapping (address => uint256) public unclaimedTokensByUser;
        event LockingPeriod(address indexed user, uint newLockingPeriod, uint newDevLockingPeriod);
        constructor(address _boneToken, address _emergencyAddress, uint256 _lockingPeriodInDays, uint256 _devLockingPeriodInDays) public {
            require(address(_boneToken) != address(0), "_bone token is a zero address");
            require(address(_emergencyAddress) != address(0), "_emergencyAddress is a zero address");
            boneToken = IERC20(_boneToken);
            emergencyAddress = _emergencyAddress;
            lockingPeriod = _lockingPeriodInDays * 1 days;
            devLockingPeriod = _devLockingPeriodInDays * 1 days;
        }
        // function to lock user reward bone tokens in token contract, called by onlyOwner that would be TopDog.sol
        function lock(address _holder, uint256 _amount, bool _isDev) external onlyOwner {
            require(_holder != address(0), "Invalid user address");
            require(_amount > 0, "Invalid amount entered");
            lockInfoByUser[_holder].push(LockInfo(_amount, now, _isDev));
            unclaimedTokensByUser[_holder] = unclaimedTokensByUser[_holder].add(_amount);
        }
        // function to claim all the tokens locked for a user, after the locking period
        function claimAllForUser(uint256 r, address user) public {
            require(!emergencyFlag, "Emergency mode, cannot access this function");
            require(r>latestCounterByUser[user], "Increase right header, already claimed till this");
            require(r<=lockInfoByUser[user].length, "Decrease right header, it exceeds total length");
            LockInfo[] memory lockInfoArrayForUser = lockInfoByUser[user];
            uint256 totalTransferableAmount = 0;
            uint i;
            for (i=latestCounterByUser[user]; i<r; i++){
                uint256 lockingPeriodHere = lockingPeriod;
                if(lockInfoArrayForUser[i]._isDev){
                    lockingPeriodHere = devLockingPeriod;
                }
                if(now >= (lockInfoArrayForUser[i]._timestamp.add(lockingPeriodHere))){
                    totalTransferableAmount = totalTransferableAmount.add(lockInfoArrayForUser[i]._amount);
                    unclaimedTokensByUser[user] = unclaimedTokensByUser[user].sub(lockInfoArrayForUser[i]._amount);
                    latestCounterByUser[user] = i.add(1);
                } else {
                    break;
                }
            }
            boneToken.transfer(user, totalTransferableAmount);
        }
        // function to claim all the tokens locked by user, after the locking period
        function claimAll(uint256 r) external {
            claimAllForUser(r, msg.sender);
        }
        // function to get claimable amount for any user
        function getClaimableAmount(address _user) external view returns(uint256) {
            LockInfo[] memory lockInfoArrayForUser = lockInfoByUser[_user];
            uint256 totalTransferableAmount = 0;
            uint i;
            for (i=latestCounterByUser[_user]; i<lockInfoArrayForUser.length; i++){
                uint256 lockingPeriodHere = lockingPeriod;
                if(lockInfoArrayForUser[i]._isDev){
                    lockingPeriodHere = devLockingPeriod;
                }
                if(now >= (lockInfoArrayForUser[i]._timestamp.add(lockingPeriodHere))){
                    totalTransferableAmount = totalTransferableAmount.add(lockInfoArrayForUser[i]._amount);
                } else {
                    break;
                }
            }
            return totalTransferableAmount;
        }
        // get the left and right headers for a user, left header is the index counter till which we have already iterated, right header is basically the length of user's lockInfo array
        function getLeftRightCounters(address _user) external view returns(uint256, uint256){
            return(latestCounterByUser[_user], lockInfoByUser[_user].length);
        }
        // in cases of emergency, emergency address can set this to true, which will enable emergencyWithdraw function
        function setEmergencyFlag(bool _emergencyFlag) external {
            require(msg.sender == emergencyAddress, "This function can only be called by emergencyAddress");
            emergencyFlag = _emergencyFlag;
        }
        // function for owner to transfer all tokens to another address
        function emergencyWithdrawOwner(address _to) external onlyOwner{
            uint256 amount = boneToken.balanceOf(address(this));
            require(boneToken.transfer(_to, amount), 'MerkleDistributor: Transfer failed.');
        }
        // emergency address can be updated from here
        function setEmergencyAddr(address _newAddr) external {
            require(msg.sender == emergencyAddress, "This function can only be called by emergencyAddress");
            require(_newAddr != address(0), "_newAddr is a zero address");
            emergencyAddress = _newAddr;
        }
        // function to update/change the normal & dev locking period
        function setLockingPeriod(uint256 _newLockingPeriod, uint256 _newDevLockingPeriod) external onlyOwner {
            lockingPeriod = _newLockingPeriod;
            devLockingPeriod = _newDevLockingPeriod;
            emit LockingPeriod(msg.sender, _newLockingPeriod, _newDevLockingPeriod);
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.2 <0.8.0;
    /**
     * @dev Collection of functions related to the address type
     */
    library Address {
        /**
         * @dev Returns true if `account` is a contract.
         *
         * [IMPORTANT]
         * ====
         * It is unsafe to assume that an address for which this function returns
         * false is an externally-owned account (EOA) and not a contract.
         *
         * Among others, `isContract` will return false for the following
         * types of addresses:
         *
         *  - an externally-owned account
         *  - a contract in construction
         *  - an address where a contract will be created
         *  - an address where a contract lived, but was destroyed
         * ====
         */
        function isContract(address account) internal view returns (bool) {
            // This method relies on extcodesize, which returns 0 for contracts in
            // construction, since the code is only stored at the end of the
            // constructor execution.
            uint256 size;
            // solhint-disable-next-line no-inline-assembly
            assembly { size := extcodesize(account) }
            return size > 0;
        }
        /**
         * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
         * `recipient`, forwarding all available gas and reverting on errors.
         *
         * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
         * of certain opcodes, possibly making contracts go over the 2300 gas limit
         * imposed by `transfer`, making them unable to receive funds via
         * `transfer`. {sendValue} removes this limitation.
         *
         * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
         *
         * IMPORTANT: because control is transferred to `recipient`, care must be
         * taken to not create reentrancy vulnerabilities. Consider using
         * {ReentrancyGuard} or the
         * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
         */
        function sendValue(address payable recipient, uint256 amount) internal {
            require(address(this).balance >= amount, "Address: insufficient balance");
            // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
            (bool success, ) = recipient.call{ value: amount }("");
            require(success, "Address: unable to send value, recipient may have reverted");
        }
        /**
         * @dev Performs a Solidity function call using a low level `call`. A
         * plain`call` is an unsafe replacement for a function call: use this
         * function instead.
         *
         * If `target` reverts with a revert reason, it is bubbled up by this
         * function (like regular Solidity function calls).
         *
         * Returns the raw returned data. To convert to the expected return value,
         * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
         *
         * Requirements:
         *
         * - `target` must be a contract.
         * - calling `target` with `data` must not revert.
         *
         * _Available since v3.1._
         */
        function functionCall(address target, bytes memory data) internal returns (bytes memory) {
          return functionCall(target, data, "Address: low-level call failed");
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
         * `errorMessage` as a fallback revert reason when `target` reverts.
         *
         * _Available since v3.1._
         */
        function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
            return functionCallWithValue(target, data, 0, errorMessage);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but also transferring `value` wei to `target`.
         *
         * Requirements:
         *
         * - the calling contract must have an ETH balance of at least `value`.
         * - the called Solidity function must be `payable`.
         *
         * _Available since v3.1._
         */
        function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
            return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
        }
        /**
         * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
         * with `errorMessage` as a fallback revert reason when `target` reverts.
         *
         * _Available since v3.1._
         */
        function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
            require(address(this).balance >= value, "Address: insufficient balance for call");
            require(isContract(target), "Address: call to non-contract");
            // solhint-disable-next-line avoid-low-level-calls
            (bool success, bytes memory returndata) = target.call{ value: value }(data);
            return _verifyCallResult(success, returndata, errorMessage);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but performing a static call.
         *
         * _Available since v3.3._
         */
        function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
            return functionStaticCall(target, data, "Address: low-level static call failed");
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
         * but performing a static call.
         *
         * _Available since v3.3._
         */
        function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
            require(isContract(target), "Address: static call to non-contract");
            // solhint-disable-next-line avoid-low-level-calls
            (bool success, bytes memory returndata) = target.staticcall(data);
            return _verifyCallResult(success, returndata, errorMessage);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but performing a delegate call.
         *
         * _Available since v3.4._
         */
        function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
            return functionDelegateCall(target, data, "Address: low-level delegate call failed");
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
         * but performing a delegate call.
         *
         * _Available since v3.4._
         */
        function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
            require(isContract(target), "Address: delegate call to non-contract");
            // solhint-disable-next-line avoid-low-level-calls
            (bool success, bytes memory returndata) = target.delegatecall(data);
            return _verifyCallResult(success, returndata, errorMessage);
        }
        function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
            if (success) {
                return returndata;
            } else {
                // Look for revert reason and bubble it up if present
                if (returndata.length > 0) {
                    // The easiest way to bubble the revert reason is using memory via assembly
                    // solhint-disable-next-line no-inline-assembly
                    assembly {
                        let returndata_size := mload(returndata)
                        revert(add(32, returndata), returndata_size)
                    }
                } else {
                    revert(errorMessage);
                }
            }
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    /*
     * @dev Provides information about the current execution context, including the
     * sender of the transaction and its data. While these are generally available
     * via msg.sender and msg.data, they should not be accessed in such a direct
     * manner, since when dealing with GSN meta-transactions the account sending and
     * paying for execution may not be the actual sender (as far as an application
     * is concerned).
     *
     * This contract is only required for intermediate, library-like contracts.
     */
    abstract contract Context {
        function _msgSender() internal view virtual returns (address payable) {
            return msg.sender;
        }
        function _msgData() internal view virtual returns (bytes memory) {
            this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
            return msg.data;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    import "../../utils/Context.sol";
    import "./IERC20.sol";
    import "../../math/SafeMath.sol";
    /**
     * @dev Implementation of the {IERC20} interface.
     *
     * This implementation is agnostic to the way tokens are created. This means
     * that a supply mechanism has to be added in a derived contract using {_mint}.
     * For a generic mechanism see {ERC20PresetMinterPauser}.
     *
     * TIP: For a detailed writeup see our guide
     * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
     * to implement supply mechanisms].
     *
     * We have followed general OpenZeppelin guidelines: functions revert instead
     * of returning `false` on failure. This behavior is nonetheless conventional
     * and does not conflict with the expectations of ERC20 applications.
     *
     * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
     * This allows applications to reconstruct the allowance for all accounts just
     * by listening to said events. Other implementations of the EIP may not emit
     * these events, as it isn't required by the specification.
     *
     * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
     * functions have been added to mitigate the well-known issues around setting
     * allowances. See {IERC20-approve}.
     */
    contract ERC20 is Context, IERC20 {
        using SafeMath for uint256;
        mapping (address => uint256) private _balances;
        mapping (address => mapping (address => uint256)) private _allowances;
        uint256 private _totalSupply;
        string private _name;
        string private _symbol;
        uint8 private _decimals;
        /**
         * @dev Sets the values for {name} and {symbol}, initializes {decimals} with
         * a default value of 18.
         *
         * To select a different value for {decimals}, use {_setupDecimals}.
         *
         * All three of these values are immutable: they can only be set once during
         * construction.
         */
        constructor (string memory name_, string memory symbol_) public {
            _name = name_;
            _symbol = symbol_;
            _decimals = 18;
        }
        /**
         * @dev Returns the name of the token.
         */
        function name() public view virtual returns (string memory) {
            return _name;
        }
        /**
         * @dev Returns the symbol of the token, usually a shorter version of the
         * name.
         */
        function symbol() public view virtual returns (string memory) {
            return _symbol;
        }
        /**
         * @dev Returns the number of decimals used to get its user representation.
         * For example, if `decimals` equals `2`, a balance of `505` tokens should
         * be displayed to a user as `5,05` (`505 / 10 ** 2`).
         *
         * Tokens usually opt for a value of 18, imitating the relationship between
         * Ether and Wei. This is the value {ERC20} uses, unless {_setupDecimals} is
         * called.
         *
         * NOTE: This information is only used for _display_ purposes: it in
         * no way affects any of the arithmetic of the contract, including
         * {IERC20-balanceOf} and {IERC20-transfer}.
         */
        function decimals() public view virtual returns (uint8) {
            return _decimals;
        }
        /**
         * @dev See {IERC20-totalSupply}.
         */
        function totalSupply() public view virtual override returns (uint256) {
            return _totalSupply;
        }
        /**
         * @dev See {IERC20-balanceOf}.
         */
        function balanceOf(address account) public view virtual override returns (uint256) {
            return _balances[account];
        }
        /**
         * @dev See {IERC20-transfer}.
         *
         * Requirements:
         *
         * - `recipient` cannot be the zero address.
         * - the caller must have a balance of at least `amount`.
         */
        function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
            _transfer(_msgSender(), recipient, amount);
            return true;
        }
        /**
         * @dev See {IERC20-allowance}.
         */
        function allowance(address owner, address spender) public view virtual override returns (uint256) {
            return _allowances[owner][spender];
        }
        /**
         * @dev See {IERC20-approve}.
         *
         * Requirements:
         *
         * - `spender` cannot be the zero address.
         */
        function approve(address spender, uint256 amount) public virtual override returns (bool) {
            _approve(_msgSender(), spender, amount);
            return true;
        }
        /**
         * @dev See {IERC20-transferFrom}.
         *
         * Emits an {Approval} event indicating the updated allowance. This is not
         * required by the EIP. See the note at the beginning of {ERC20}.
         *
         * Requirements:
         *
         * - `sender` and `recipient` cannot be the zero address.
         * - `sender` must have a balance of at least `amount`.
         * - the caller must have allowance for ``sender``'s tokens of at least
         * `amount`.
         */
        function transferFrom(address sender, address recipient, uint256 amount) public virtual override returns (bool) {
            _transfer(sender, recipient, amount);
            _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
            return true;
        }
        /**
         * @dev Atomically increases the allowance granted to `spender` by the caller.
         *
         * This is an alternative to {approve} that can be used as a mitigation for
         * problems described in {IERC20-approve}.
         *
         * Emits an {Approval} event indicating the updated allowance.
         *
         * Requirements:
         *
         * - `spender` cannot be the zero address.
         */
        function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
            _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
            return true;
        }
        /**
         * @dev Atomically decreases the allowance granted to `spender` by the caller.
         *
         * This is an alternative to {approve} that can be used as a mitigation for
         * problems described in {IERC20-approve}.
         *
         * Emits an {Approval} event indicating the updated allowance.
         *
         * Requirements:
         *
         * - `spender` cannot be the zero address.
         * - `spender` must have allowance for the caller of at least
         * `subtractedValue`.
         */
        function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
            _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
            return true;
        }
        /**
         * @dev Moves tokens `amount` from `sender` to `recipient`.
         *
         * This is internal function is equivalent to {transfer}, and can be used to
         * e.g. implement automatic token fees, slashing mechanisms, etc.
         *
         * Emits a {Transfer} event.
         *
         * Requirements:
         *
         * - `sender` cannot be the zero address.
         * - `recipient` cannot be the zero address.
         * - `sender` must have a balance of at least `amount`.
         */
        function _transfer(address sender, address recipient, uint256 amount) internal virtual {
            require(sender != address(0), "ERC20: transfer from the zero address");
            require(recipient != address(0), "ERC20: transfer to the zero address");
            _beforeTokenTransfer(sender, recipient, amount);
            _balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance");
            _balances[recipient] = _balances[recipient].add(amount);
            emit Transfer(sender, recipient, amount);
        }
        /** @dev Creates `amount` tokens and assigns them to `account`, increasing
         * the total supply.
         *
         * Emits a {Transfer} event with `from` set to the zero address.
         *
         * Requirements:
         *
         * - `to` cannot be the zero address.
         */
        function _mint(address account, uint256 amount) internal virtual {
            require(account != address(0), "ERC20: mint to the zero address");
            _beforeTokenTransfer(address(0), account, amount);
            _totalSupply = _totalSupply.add(amount);
            _balances[account] = _balances[account].add(amount);
            emit Transfer(address(0), account, amount);
        }
        /**
         * @dev Destroys `amount` tokens from `account`, reducing the
         * total supply.
         *
         * Emits a {Transfer} event with `to` set to the zero address.
         *
         * Requirements:
         *
         * - `account` cannot be the zero address.
         * - `account` must have at least `amount` tokens.
         */
        function _burn(address account, uint256 amount) internal virtual {
            require(account != address(0), "ERC20: burn from the zero address");
            _beforeTokenTransfer(account, address(0), amount);
            _balances[account] = _balances[account].sub(amount, "ERC20: burn amount exceeds balance");
            _totalSupply = _totalSupply.sub(amount);
            emit Transfer(account, address(0), amount);
        }
        /**
         * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
         *
         * This internal function is equivalent to `approve`, and can be used to
         * e.g. set automatic allowances for certain subsystems, etc.
         *
         * Emits an {Approval} event.
         *
         * Requirements:
         *
         * - `owner` cannot be the zero address.
         * - `spender` cannot be the zero address.
         */
        function _approve(address owner, address spender, uint256 amount) internal virtual {
            require(owner != address(0), "ERC20: approve from the zero address");
            require(spender != address(0), "ERC20: approve to the zero address");
            _allowances[owner][spender] = amount;
            emit Approval(owner, spender, amount);
        }
        /**
         * @dev Sets {decimals} to a value other than the default one of 18.
         *
         * WARNING: This function should only be called from the constructor. Most
         * applications that interact with token contracts will not expect
         * {decimals} to ever change, and may work incorrectly if it does.
         */
        function _setupDecimals(uint8 decimals_) internal virtual {
            _decimals = decimals_;
        }
        /**
         * @dev Hook that is called before any transfer of tokens. This includes
         * minting and burning.
         *
         * Calling conditions:
         *
         * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
         * will be to transferred to `to`.
         * - when `from` is zero, `amount` tokens will be minted for `to`.
         * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
         * - `from` and `to` are never both zero.
         *
         * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
         */
        function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual { }
    }
    

    File 2 of 8: DevBoneDistributor
    // SPDX-License-Identifier: MIT
    pragma solidity 0.6.12;
    import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
    import "@openzeppelin/contracts/math/SafeMath.sol";
    import "@openzeppelin/contracts/access/Ownable.sol";
    import "./BoneLocker.sol";
    contract DevBoneDistributor is Ownable {
        using SafeMath for uint256;
        IERC20 public bone;
        BoneLocker public boneLocker;
        address public devWallet;
        address public marketingAndGrowthWallet;
        uint256 public devSharePercent;
        uint256 public marketingAndGrowthSharePercent;
        event WalletUpdated(string wallet, address indexed user, address newAddr);
        event DistributionUpdated(uint devSharePercent, uint marketingAndGrowthSharePercent);
        constructor (
            IERC20 _bone,
            BoneLocker _boneLocker,
            address _devWallet,
            address _marketingAndGrowthWallet
        ) public {
            require(address(_bone) != address(0), "_bone is a zero address");
            require(address(_boneLocker) != address(0), "_boneLocker is a zero address");
            bone = _bone;
            boneLocker = _boneLocker;
            devWallet = _devWallet;
            marketingAndGrowthWallet = _marketingAndGrowthWallet;
            devSharePercent = 80;
            marketingAndGrowthSharePercent = 20;
        }
        function boneBalance() external view returns(uint) {
            return bone.balanceOf(address(this));
        }
        function setDevWallet(address _devWallet)  external onlyOwner {
            devWallet = _devWallet;
            emit WalletUpdated("Dev Wallet", msg.sender, _devWallet);
        }
        function setMarketingAndGrowthWallet(address _marketingAndGrowthWallet)  external onlyOwner {
            marketingAndGrowthWallet = _marketingAndGrowthWallet;
            emit WalletUpdated("Marketing and Growth Wallet", msg.sender, _marketingAndGrowthWallet);
        }
        function setWalletDistribution(uint _devSharePercent, uint _marketingAndGrowthSharePercent)  external onlyOwner {
            require(_devSharePercent.add(_marketingAndGrowthSharePercent) == 100, "distributor: Incorrect percentages");
            devSharePercent = _devSharePercent;
            marketingAndGrowthSharePercent = _marketingAndGrowthSharePercent;
            emit DistributionUpdated(_devSharePercent, _marketingAndGrowthSharePercent);
        }
        function distribute(uint256 _total) external onlyOwner {
            require(_total > 0, "No BONE to distribute");
            uint devWalletShare = _total.mul(devSharePercent).div(100);
            uint marketingAndGrowthWalletShare = _total.sub(devWalletShare);
            require(bone.transfer(devWallet, devWalletShare), "transfer: devWallet failed");
            require(bone.transfer(marketingAndGrowthWallet, marketingAndGrowthWalletShare), "transfer: marketingAndGrowthWallet failed");
        }
        // funtion to claim the locked tokens for devBoneDistributor, which will transfer the locked tokens for dev to devAddr after the devLockingPeriod
        function claimLockedTokens(uint256 r) external onlyOwner {
            boneLocker.claimAll(r);
        }
        // Update boneLocker address by the owner.
        function boneLockerUpdate(address _boneLocker) public onlyOwner {
            boneLocker = BoneLocker(_boneLocker);
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    /**
     * @dev Interface of the ERC20 standard as defined in the EIP.
     */
    interface IERC20 {
        /**
         * @dev Returns the amount of tokens in existence.
         */
        function totalSupply() external view returns (uint256);
        /**
         * @dev Returns the amount of tokens owned by `account`.
         */
        function balanceOf(address account) external view returns (uint256);
        /**
         * @dev Moves `amount` tokens from the caller's account to `recipient`.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transfer(address recipient, uint256 amount) external returns (bool);
        /**
         * @dev Returns the remaining number of tokens that `spender` will be
         * allowed to spend on behalf of `owner` through {transferFrom}. This is
         * zero by default.
         *
         * This value changes when {approve} or {transferFrom} are called.
         */
        function allowance(address owner, address spender) external view returns (uint256);
        /**
         * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * IMPORTANT: Beware that changing an allowance with this method brings the risk
         * that someone may use both the old and the new allowance by unfortunate
         * transaction ordering. One possible solution to mitigate this race
         * condition is to first reduce the spender's allowance to 0 and set the
         * desired value afterwards:
         * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
         *
         * Emits an {Approval} event.
         */
        function approve(address spender, uint256 amount) external returns (bool);
        /**
         * @dev Moves `amount` tokens from `sender` to `recipient` using the
         * allowance mechanism. `amount` is then deducted from the caller's
         * allowance.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
        /**
         * @dev Emitted when `value` tokens are moved from one account (`from`) to
         * another (`to`).
         *
         * Note that `value` may be zero.
         */
        event Transfer(address indexed from, address indexed to, uint256 value);
        /**
         * @dev Emitted when the allowance of a `spender` for an `owner` is set by
         * a call to {approve}. `value` is the new allowance.
         */
        event Approval(address indexed owner, address indexed spender, uint256 value);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    /**
     * @dev Wrappers over Solidity's arithmetic operations with added overflow
     * checks.
     *
     * Arithmetic operations in Solidity wrap on overflow. This can easily result
     * in bugs, because programmers usually assume that an overflow raises an
     * error, which is the standard behavior in high level programming languages.
     * `SafeMath` restores this intuition by reverting the transaction when an
     * operation overflows.
     *
     * Using this library instead of the unchecked operations eliminates an entire
     * class of bugs, so it's recommended to use it always.
     */
    library SafeMath {
        /**
         * @dev Returns the addition of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
        /**
         * @dev Returns the substraction of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
        /**
         * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
            // benefit is lost if 'b' is also tested.
            // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
            if (a == 0) return (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
        /**
         * @dev Returns the division of two unsigned integers, with a division by zero flag.
         *
         * _Available since v3.4._
         */
        function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
         *
         * _Available since v3.4._
         */
        function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
        /**
         * @dev Returns the addition of two unsigned integers, reverting on
         * overflow.
         *
         * Counterpart to Solidity's `+` operator.
         *
         * Requirements:
         *
         * - Addition cannot overflow.
         */
        function add(uint256 a, uint256 b) internal pure returns (uint256) {
            uint256 c = a + b;
            require(c >= a, "SafeMath: addition overflow");
            return c;
        }
        /**
         * @dev Returns the subtraction of two unsigned integers, reverting on
         * overflow (when the result is negative).
         *
         * Counterpart to Solidity's `-` operator.
         *
         * Requirements:
         *
         * - Subtraction cannot overflow.
         */
        function sub(uint256 a, uint256 b) internal pure returns (uint256) {
            require(b <= a, "SafeMath: subtraction overflow");
            return a - b;
        }
        /**
         * @dev Returns the multiplication of two unsigned integers, reverting on
         * overflow.
         *
         * Counterpart to Solidity's `*` operator.
         *
         * Requirements:
         *
         * - Multiplication cannot overflow.
         */
        function mul(uint256 a, uint256 b) internal pure returns (uint256) {
            if (a == 0) return 0;
            uint256 c = a * b;
            require(c / a == b, "SafeMath: multiplication overflow");
            return c;
        }
        /**
         * @dev Returns the integer division of two unsigned integers, reverting on
         * division by zero. The result is rounded towards zero.
         *
         * Counterpart to Solidity's `/` operator. Note: this function uses a
         * `revert` opcode (which leaves remaining gas untouched) while Solidity
         * uses an invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function div(uint256 a, uint256 b) internal pure returns (uint256) {
            require(b > 0, "SafeMath: division by zero");
            return a / b;
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
         * reverting when dividing by zero.
         *
         * Counterpart to Solidity's `%` operator. This function uses a `revert`
         * opcode (which leaves remaining gas untouched) while Solidity uses an
         * invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function mod(uint256 a, uint256 b) internal pure returns (uint256) {
            require(b > 0, "SafeMath: modulo by zero");
            return a % b;
        }
        /**
         * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
         * overflow (when the result is negative).
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {trySub}.
         *
         * Counterpart to Solidity's `-` operator.
         *
         * Requirements:
         *
         * - Subtraction cannot overflow.
         */
        function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
            require(b <= a, errorMessage);
            return a - b;
        }
        /**
         * @dev Returns the integer division of two unsigned integers, reverting with custom message on
         * division by zero. The result is rounded towards zero.
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {tryDiv}.
         *
         * Counterpart to Solidity's `/` operator. Note: this function uses a
         * `revert` opcode (which leaves remaining gas untouched) while Solidity
         * uses an invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
            require(b > 0, errorMessage);
            return a / b;
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
         * reverting with custom message when dividing by zero.
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {tryMod}.
         *
         * Counterpart to Solidity's `%` operator. This function uses a `revert`
         * opcode (which leaves remaining gas untouched) while Solidity uses an
         * invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    import "../utils/Context.sol";
    /**
     * @dev Contract module which provides a basic access control mechanism, where
     * there is an account (an owner) that can be granted exclusive access to
     * specific functions.
     *
     * By default, the owner account will be the one that deploys the contract. This
     * can later be changed with {transferOwnership}.
     *
     * This module is used through inheritance. It will make available the modifier
     * `onlyOwner`, which can be applied to your functions to restrict their use to
     * the owner.
     */
    abstract contract Ownable is Context {
        address private _owner;
        event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
        /**
         * @dev Initializes the contract setting the deployer as the initial owner.
         */
        constructor () internal {
            address msgSender = _msgSender();
            _owner = msgSender;
            emit OwnershipTransferred(address(0), msgSender);
        }
        /**
         * @dev Returns the address of the current owner.
         */
        function owner() public view virtual returns (address) {
            return _owner;
        }
        /**
         * @dev Throws if called by any account other than the owner.
         */
        modifier onlyOwner() {
            require(owner() == _msgSender(), "Ownable: caller is not the owner");
            _;
        }
        /**
         * @dev Leaves the contract without owner. It will not be possible to call
         * `onlyOwner` functions anymore. Can only be called by the current owner.
         *
         * NOTE: Renouncing ownership will leave the contract without an owner,
         * thereby removing any functionality that is only available to the owner.
         */
        function renounceOwnership() public virtual onlyOwner {
            emit OwnershipTransferred(_owner, address(0));
            _owner = address(0);
        }
        /**
         * @dev Transfers ownership of the contract to a new account (`newOwner`).
         * Can only be called by the current owner.
         */
        function transferOwnership(address newOwner) public virtual onlyOwner {
            require(newOwner != address(0), "Ownable: new owner is the zero address");
            emit OwnershipTransferred(_owner, newOwner);
            _owner = newOwner;
        }
    }
    // SPDX-License-Identifier: UNLICENSED
    pragma solidity 0.6.12;
    import "@openzeppelin/contracts/access/Ownable.sol";
    import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
    import "@openzeppelin/contracts/math/SafeMath.sol";
    // BoneToken locker contract.
    contract BoneLocker is Ownable {
        using SafeMath for uint256;
        IERC20 boneToken;
        address emergencyAddress;
        bool emergencyFlag = false;
        struct LockInfo{
            uint256 _amount;
            uint256 _timestamp;
            bool _isDev;
        }
        uint256 public lockingPeriod;
        uint256 public devLockingPeriod;
        mapping (address => LockInfo[]) public lockInfoByUser;
        mapping (address => uint256) public latestCounterByUser;
        mapping (address => uint256) public unclaimedTokensByUser;
        event LockingPeriod(address indexed user, uint newLockingPeriod, uint newDevLockingPeriod);
        constructor(address _boneToken, address _emergencyAddress, uint256 _lockingPeriodInDays, uint256 _devLockingPeriodInDays) public {
            require(address(_boneToken) != address(0), "_bone token is a zero address");
            require(address(_emergencyAddress) != address(0), "_emergencyAddress is a zero address");
            boneToken = IERC20(_boneToken);
            emergencyAddress = _emergencyAddress;
            lockingPeriod = _lockingPeriodInDays * 1 days;
            devLockingPeriod = _devLockingPeriodInDays * 1 days;
        }
        // function to lock user reward bone tokens in token contract, called by onlyOwner that would be TopDog.sol
        function lock(address _holder, uint256 _amount, bool _isDev) external onlyOwner {
            require(_holder != address(0), "Invalid user address");
            require(_amount > 0, "Invalid amount entered");
            lockInfoByUser[_holder].push(LockInfo(_amount, now, _isDev));
            unclaimedTokensByUser[_holder] = unclaimedTokensByUser[_holder].add(_amount);
        }
        // function to claim all the tokens locked for a user, after the locking period
        function claimAllForUser(uint256 r, address user) public {
            require(!emergencyFlag, "Emergency mode, cannot access this function");
            require(r>latestCounterByUser[user], "Increase right header, already claimed till this");
            require(r<=lockInfoByUser[user].length, "Decrease right header, it exceeds total length");
            LockInfo[] memory lockInfoArrayForUser = lockInfoByUser[user];
            uint256 totalTransferableAmount = 0;
            uint i;
            for (i=latestCounterByUser[user]; i<r; i++){
                uint256 lockingPeriodHere = lockingPeriod;
                if(lockInfoArrayForUser[i]._isDev){
                    lockingPeriodHere = devLockingPeriod;
                }
                if(now >= (lockInfoArrayForUser[i]._timestamp.add(lockingPeriodHere))){
                    totalTransferableAmount = totalTransferableAmount.add(lockInfoArrayForUser[i]._amount);
                    unclaimedTokensByUser[user] = unclaimedTokensByUser[user].sub(lockInfoArrayForUser[i]._amount);
                    latestCounterByUser[user] = i.add(1);
                } else {
                    break;
                }
            }
            boneToken.transfer(user, totalTransferableAmount);
        }
        // function to claim all the tokens locked by user, after the locking period
        function claimAll(uint256 r) external {
            claimAllForUser(r, msg.sender);
        }
        // function to get claimable amount for any user
        function getClaimableAmount(address _user) external view returns(uint256) {
            LockInfo[] memory lockInfoArrayForUser = lockInfoByUser[_user];
            uint256 totalTransferableAmount = 0;
            uint i;
            for (i=latestCounterByUser[_user]; i<lockInfoArrayForUser.length; i++){
                uint256 lockingPeriodHere = lockingPeriod;
                if(lockInfoArrayForUser[i]._isDev){
                    lockingPeriodHere = devLockingPeriod;
                }
                if(now >= (lockInfoArrayForUser[i]._timestamp.add(lockingPeriodHere))){
                    totalTransferableAmount = totalTransferableAmount.add(lockInfoArrayForUser[i]._amount);
                } else {
                    break;
                }
            }
            return totalTransferableAmount;
        }
        // get the left and right headers for a user, left header is the index counter till which we have already iterated, right header is basically the length of user's lockInfo array
        function getLeftRightCounters(address _user) external view returns(uint256, uint256){
            return(latestCounterByUser[_user], lockInfoByUser[_user].length);
        }
        // in cases of emergency, emergency address can set this to true, which will enable emergencyWithdraw function
        function setEmergencyFlag(bool _emergencyFlag) external {
            require(msg.sender == emergencyAddress, "This function can only be called by emergencyAddress");
            emergencyFlag = _emergencyFlag;
        }
        // function for owner to transfer all tokens to another address
        function emergencyWithdrawOwner(address _to) external onlyOwner{
            uint256 amount = boneToken.balanceOf(address(this));
            require(boneToken.transfer(_to, amount), 'MerkleDistributor: Transfer failed.');
        }
        // emergency address can be updated from here
        function setEmergencyAddr(address _newAddr) external {
            require(msg.sender == emergencyAddress, "This function can only be called by emergencyAddress");
            require(_newAddr != address(0), "_newAddr is a zero address");
            emergencyAddress = _newAddr;
        }
        // function to update/change the normal & dev locking period
        function setLockingPeriod(uint256 _newLockingPeriod, uint256 _newDevLockingPeriod) external onlyOwner {
            lockingPeriod = _newLockingPeriod;
            devLockingPeriod = _newDevLockingPeriod;
            emit LockingPeriod(msg.sender, _newLockingPeriod, _newDevLockingPeriod);
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    /*
     * @dev Provides information about the current execution context, including the
     * sender of the transaction and its data. While these are generally available
     * via msg.sender and msg.data, they should not be accessed in such a direct
     * manner, since when dealing with GSN meta-transactions the account sending and
     * paying for execution may not be the actual sender (as far as an application
     * is concerned).
     *
     * This contract is only required for intermediate, library-like contracts.
     */
    abstract contract Context {
        function _msgSender() internal view virtual returns (address payable) {
            return msg.sender;
        }
        function _msgData() internal view virtual returns (bytes memory) {
            this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
            return msg.data;
        }
    }
    

    File 3 of 8: BoneToken
    // SPDX-License-Identifier: MIT
    pragma solidity 0.6.12;
    import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
    import "@openzeppelin/contracts/access/Ownable.sol";
    // BoneToken with Governance.
    contract BoneToken is ERC20("BONE SHIBASWAP", "BONE"), Ownable {
        /// @notice Creates `_amount` token to `_to`. Must only be called by the owner (TopDog).
        function mint(address _to, uint256 _amount) public onlyOwner {
            _mint(_to, _amount);
            _moveDelegates(address(0), _delegates[_to], _amount);
        }
        function _transfer(address sender, address recipient, uint256 amount) internal override {
            super._transfer(sender, recipient, amount);
            _moveDelegates(_delegates[sender], _delegates[recipient], amount);
        }
        // Copied and modified from YAM code:
        // https://github.com/yam-finance/yam-protocol/blob/master/contracts/token/YAMGovernanceStorage.sol
        // https://github.com/yam-finance/yam-protocol/blob/master/contracts/token/YAMGovernance.sol
        // Which is copied and modified from COMPOUND:
        // https://github.com/compound-finance/compound-protocol/blob/master/contracts/Governance/Comp.sol
        /// @dev A record of each accounts delegate
        mapping (address => address) internal _delegates;
        /// @notice A checkpoint for marking number of votes from a given block
        struct Checkpoint {
            uint32 fromBlock;
            uint256 votes;
        }
        /// @notice A record of votes checkpoints for each account, by index
        mapping (address => mapping (uint32 => Checkpoint)) public checkpoints;
        /// @notice The number of checkpoints for each account
        mapping (address => uint32) public numCheckpoints;
        /// @notice The EIP-712 typehash for the contract's domain
        bytes32 public constant DOMAIN_TYPEHASH = keccak256("EIP712Domain(string name,uint256 chainId,address verifyingContract)");
        /// @notice The EIP-712 typehash for the delegation struct used by the contract
        bytes32 public constant DELEGATION_TYPEHASH = keccak256("Delegation(address delegatee,uint256 nonce,uint256 expiry)");
        /// @notice A record of states for signing / validating signatures
        mapping (address => uint) public nonces;
          /// @notice An event thats emitted when an account changes its delegate
        event DelegateChanged(address indexed delegator, address indexed fromDelegate, address indexed toDelegate);
        /// @notice An event thats emitted when a delegate account's vote balance changes
        event DelegateVotesChanged(address indexed delegate, uint previousBalance, uint newBalance);
        /**
         * @notice Delegate votes from `msg.sender` to `delegatee`
         * @param delegator The address to get delegatee for
         */
        function delegates(address delegator)
            external
            view
            returns (address)
        {
            return _delegates[delegator];
        }
       /**
        * @notice Delegate votes from `msg.sender` to `delegatee`
        * @param delegatee The address to delegate votes to
        */
        function delegate(address delegatee) external {
            return _delegate(msg.sender, delegatee);
        }
        /**
         * @notice Delegates votes from signatory to `delegatee`
         * @param delegatee The address to delegate votes to
         * @param nonce The contract state required to match the signature
         * @param expiry The time at which to expire the signature
         * @param v The recovery byte of the signature
         * @param r Half of the ECDSA signature pair
         * @param s Half of the ECDSA signature pair
         */
        function delegateBySig(
            address delegatee,
            uint nonce,
            uint expiry,
            uint8 v,
            bytes32 r,
            bytes32 s
        )
            external
        {
            bytes32 domainSeparator = keccak256(
                abi.encode(
                    DOMAIN_TYPEHASH,
                    keccak256(bytes(name())),
                    getChainId(),
                    address(this)
                )
            );
            bytes32 structHash = keccak256(
                abi.encode(
                    DELEGATION_TYPEHASH,
                    delegatee,
                    nonce,
                    expiry
                )
            );
            bytes32 digest = keccak256(
                abi.encodePacked(
                    "\\x19\\x01",
                    domainSeparator,
                    structHash
                )
            );
            address signatory = ecrecover(digest, v, r, s);
            require(signatory != address(0), "BONE::delegateBySig: invalid signature");
            require(nonce == nonces[signatory]++, "BONE::delegateBySig: invalid nonce");
            require(now <= expiry, "BONE::delegateBySig: signature expired");
            return _delegate(signatory, delegatee);
        }
        /**
         * @notice Gets the current votes balance for `account`
         * @param account The address to get votes balance
         * @return The number of current votes for `account`
         */
        function getCurrentVotes(address account)
            external
            view
            returns (uint256)
        {
            uint32 nCheckpoints = numCheckpoints[account];
            return nCheckpoints > 0 ? checkpoints[account][nCheckpoints - 1].votes : 0;
        }
        /**
         * @notice Determine the prior number of votes for an account as of a block number
         * @dev Block number must be a finalized block or else this function will revert to prevent misinformation.
         * @param account The address of the account to check
         * @param blockNumber The block number to get the vote balance at
         * @return The number of votes the account had as of the given block
         */
        function getPriorVotes(address account, uint blockNumber)
            external
            view
            returns (uint256)
        {
            require(blockNumber < block.number, "BONE::getPriorVotes: not yet determined");
            uint32 nCheckpoints = numCheckpoints[account];
            if (nCheckpoints == 0) {
                return 0;
            }
            // First check most recent balance
            if (checkpoints[account][nCheckpoints - 1].fromBlock <= blockNumber) {
                return checkpoints[account][nCheckpoints - 1].votes;
            }
            // Next check implicit zero balance
            if (checkpoints[account][0].fromBlock > blockNumber) {
                return 0;
            }
            uint32 lower = 0;
            uint32 upper = nCheckpoints - 1;
            while (upper > lower) {
                uint32 center = upper - (upper - lower) / 2; // ceil, avoiding overflow
                Checkpoint memory cp = checkpoints[account][center];
                if (cp.fromBlock == blockNumber) {
                    return cp.votes;
                } else if (cp.fromBlock < blockNumber) {
                    lower = center;
                } else {
                    upper = center - 1;
                }
            }
            return checkpoints[account][lower].votes;
        }
        function _delegate(address delegator, address delegatee)
            internal
        {
            address currentDelegate = _delegates[delegator];
            uint256 delegatorBalance = balanceOf(delegator); // balance of underlying BONEs (not scaled);
            _delegates[delegator] = delegatee;
            emit DelegateChanged(delegator, currentDelegate, delegatee);
            _moveDelegates(currentDelegate, delegatee, delegatorBalance);
        }
        function _moveDelegates(address srcRep, address dstRep, uint256 amount) internal {
            if (srcRep != dstRep && amount > 0) {
                if (srcRep != address(0)) {
                    // decrease old representative
                    uint32 srcRepNum = numCheckpoints[srcRep];
                    uint256 srcRepOld = srcRepNum > 0 ? checkpoints[srcRep][srcRepNum - 1].votes : 0;
                    uint256 srcRepNew = srcRepOld.sub(amount);
                    _writeCheckpoint(srcRep, srcRepNum, srcRepOld, srcRepNew);
                }
                if (dstRep != address(0)) {
                    // increase new representative
                    uint32 dstRepNum = numCheckpoints[dstRep];
                    uint256 dstRepOld = dstRepNum > 0 ? checkpoints[dstRep][dstRepNum - 1].votes : 0;
                    uint256 dstRepNew = dstRepOld.add(amount);
                    _writeCheckpoint(dstRep, dstRepNum, dstRepOld, dstRepNew);
                }
            }
        }
        function _writeCheckpoint(
            address delegatee,
            uint32 nCheckpoints,
            uint256 oldVotes,
            uint256 newVotes
        )
            internal
        {
            uint32 blockNumber = safe32(block.number, "BONE::_writeCheckpoint: block number exceeds 32 bits");
            if (nCheckpoints > 0 && checkpoints[delegatee][nCheckpoints - 1].fromBlock == blockNumber) {
                checkpoints[delegatee][nCheckpoints - 1].votes = newVotes;
            } else {
                checkpoints[delegatee][nCheckpoints] = Checkpoint(blockNumber, newVotes);
                require(nCheckpoints + 1 > nCheckpoints, "BONE::_writeCheckpoint: new checkpoint exceeds 32 bits");
                numCheckpoints[delegatee] = nCheckpoints + 1;
            }
            emit DelegateVotesChanged(delegatee, oldVotes, newVotes);
        }
        function safe32(uint n, string memory errorMessage) internal pure returns (uint32) {
            require(n < 2**32, errorMessage);
            return uint32(n);
        }
        function getChainId() internal pure returns (uint) {
            uint256 chainId;
            assembly { chainId := chainid() }
            return chainId;
        }
    }// SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    import "../../utils/Context.sol";
    import "./IERC20.sol";
    import "../../math/SafeMath.sol";
    /**
     * @dev Implementation of the {IERC20} interface.
     *
     * This implementation is agnostic to the way tokens are created. This means
     * that a supply mechanism has to be added in a derived contract using {_mint}.
     * For a generic mechanism see {ERC20PresetMinterPauser}.
     *
     * TIP: For a detailed writeup see our guide
     * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
     * to implement supply mechanisms].
     *
     * We have followed general OpenZeppelin guidelines: functions revert instead
     * of returning `false` on failure. This behavior is nonetheless conventional
     * and does not conflict with the expectations of ERC20 applications.
     *
     * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
     * This allows applications to reconstruct the allowance for all accounts just
     * by listening to said events. Other implementations of the EIP may not emit
     * these events, as it isn't required by the specification.
     *
     * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
     * functions have been added to mitigate the well-known issues around setting
     * allowances. See {IERC20-approve}.
     */
    contract ERC20 is Context, IERC20 {
        using SafeMath for uint256;
        mapping (address => uint256) private _balances;
        mapping (address => mapping (address => uint256)) private _allowances;
        uint256 private _totalSupply;
        string private _name;
        string private _symbol;
        uint8 private _decimals;
        /**
         * @dev Sets the values for {name} and {symbol}, initializes {decimals} with
         * a default value of 18.
         *
         * To select a different value for {decimals}, use {_setupDecimals}.
         *
         * All three of these values are immutable: they can only be set once during
         * construction.
         */
        constructor (string memory name_, string memory symbol_) public {
            _name = name_;
            _symbol = symbol_;
            _decimals = 18;
        }
        /**
         * @dev Returns the name of the token.
         */
        function name() public view virtual returns (string memory) {
            return _name;
        }
        /**
         * @dev Returns the symbol of the token, usually a shorter version of the
         * name.
         */
        function symbol() public view virtual returns (string memory) {
            return _symbol;
        }
        /**
         * @dev Returns the number of decimals used to get its user representation.
         * For example, if `decimals` equals `2`, a balance of `505` tokens should
         * be displayed to a user as `5,05` (`505 / 10 ** 2`).
         *
         * Tokens usually opt for a value of 18, imitating the relationship between
         * Ether and Wei. This is the value {ERC20} uses, unless {_setupDecimals} is
         * called.
         *
         * NOTE: This information is only used for _display_ purposes: it in
         * no way affects any of the arithmetic of the contract, including
         * {IERC20-balanceOf} and {IERC20-transfer}.
         */
        function decimals() public view virtual returns (uint8) {
            return _decimals;
        }
        /**
         * @dev See {IERC20-totalSupply}.
         */
        function totalSupply() public view virtual override returns (uint256) {
            return _totalSupply;
        }
        /**
         * @dev See {IERC20-balanceOf}.
         */
        function balanceOf(address account) public view virtual override returns (uint256) {
            return _balances[account];
        }
        /**
         * @dev See {IERC20-transfer}.
         *
         * Requirements:
         *
         * - `recipient` cannot be the zero address.
         * - the caller must have a balance of at least `amount`.
         */
        function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
            _transfer(_msgSender(), recipient, amount);
            return true;
        }
        /**
         * @dev See {IERC20-allowance}.
         */
        function allowance(address owner, address spender) public view virtual override returns (uint256) {
            return _allowances[owner][spender];
        }
        /**
         * @dev See {IERC20-approve}.
         *
         * Requirements:
         *
         * - `spender` cannot be the zero address.
         */
        function approve(address spender, uint256 amount) public virtual override returns (bool) {
            _approve(_msgSender(), spender, amount);
            return true;
        }
        /**
         * @dev See {IERC20-transferFrom}.
         *
         * Emits an {Approval} event indicating the updated allowance. This is not
         * required by the EIP. See the note at the beginning of {ERC20}.
         *
         * Requirements:
         *
         * - `sender` and `recipient` cannot be the zero address.
         * - `sender` must have a balance of at least `amount`.
         * - the caller must have allowance for ``sender``'s tokens of at least
         * `amount`.
         */
        function transferFrom(address sender, address recipient, uint256 amount) public virtual override returns (bool) {
            _transfer(sender, recipient, amount);
            _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
            return true;
        }
        /**
         * @dev Atomically increases the allowance granted to `spender` by the caller.
         *
         * This is an alternative to {approve} that can be used as a mitigation for
         * problems described in {IERC20-approve}.
         *
         * Emits an {Approval} event indicating the updated allowance.
         *
         * Requirements:
         *
         * - `spender` cannot be the zero address.
         */
        function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
            _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
            return true;
        }
        /**
         * @dev Atomically decreases the allowance granted to `spender` by the caller.
         *
         * This is an alternative to {approve} that can be used as a mitigation for
         * problems described in {IERC20-approve}.
         *
         * Emits an {Approval} event indicating the updated allowance.
         *
         * Requirements:
         *
         * - `spender` cannot be the zero address.
         * - `spender` must have allowance for the caller of at least
         * `subtractedValue`.
         */
        function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
            _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
            return true;
        }
        /**
         * @dev Moves tokens `amount` from `sender` to `recipient`.
         *
         * This is internal function is equivalent to {transfer}, and can be used to
         * e.g. implement automatic token fees, slashing mechanisms, etc.
         *
         * Emits a {Transfer} event.
         *
         * Requirements:
         *
         * - `sender` cannot be the zero address.
         * - `recipient` cannot be the zero address.
         * - `sender` must have a balance of at least `amount`.
         */
        function _transfer(address sender, address recipient, uint256 amount) internal virtual {
            require(sender != address(0), "ERC20: transfer from the zero address");
            require(recipient != address(0), "ERC20: transfer to the zero address");
            _beforeTokenTransfer(sender, recipient, amount);
            _balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance");
            _balances[recipient] = _balances[recipient].add(amount);
            emit Transfer(sender, recipient, amount);
        }
        /** @dev Creates `amount` tokens and assigns them to `account`, increasing
         * the total supply.
         *
         * Emits a {Transfer} event with `from` set to the zero address.
         *
         * Requirements:
         *
         * - `to` cannot be the zero address.
         */
        function _mint(address account, uint256 amount) internal virtual {
            require(account != address(0), "ERC20: mint to the zero address");
            _beforeTokenTransfer(address(0), account, amount);
            _totalSupply = _totalSupply.add(amount);
            _balances[account] = _balances[account].add(amount);
            emit Transfer(address(0), account, amount);
        }
        /**
         * @dev Destroys `amount` tokens from `account`, reducing the
         * total supply.
         *
         * Emits a {Transfer} event with `to` set to the zero address.
         *
         * Requirements:
         *
         * - `account` cannot be the zero address.
         * - `account` must have at least `amount` tokens.
         */
        function _burn(address account, uint256 amount) internal virtual {
            require(account != address(0), "ERC20: burn from the zero address");
            _beforeTokenTransfer(account, address(0), amount);
            _balances[account] = _balances[account].sub(amount, "ERC20: burn amount exceeds balance");
            _totalSupply = _totalSupply.sub(amount);
            emit Transfer(account, address(0), amount);
        }
        /**
         * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
         *
         * This internal function is equivalent to `approve`, and can be used to
         * e.g. set automatic allowances for certain subsystems, etc.
         *
         * Emits an {Approval} event.
         *
         * Requirements:
         *
         * - `owner` cannot be the zero address.
         * - `spender` cannot be the zero address.
         */
        function _approve(address owner, address spender, uint256 amount) internal virtual {
            require(owner != address(0), "ERC20: approve from the zero address");
            require(spender != address(0), "ERC20: approve to the zero address");
            _allowances[owner][spender] = amount;
            emit Approval(owner, spender, amount);
        }
        /**
         * @dev Sets {decimals} to a value other than the default one of 18.
         *
         * WARNING: This function should only be called from the constructor. Most
         * applications that interact with token contracts will not expect
         * {decimals} to ever change, and may work incorrectly if it does.
         */
        function _setupDecimals(uint8 decimals_) internal virtual {
            _decimals = decimals_;
        }
        /**
         * @dev Hook that is called before any transfer of tokens. This includes
         * minting and burning.
         *
         * Calling conditions:
         *
         * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
         * will be to transferred to `to`.
         * - when `from` is zero, `amount` tokens will be minted for `to`.
         * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
         * - `from` and `to` are never both zero.
         *
         * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
         */
        function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual { }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    import "../utils/Context.sol";
    /**
     * @dev Contract module which provides a basic access control mechanism, where
     * there is an account (an owner) that can be granted exclusive access to
     * specific functions.
     *
     * By default, the owner account will be the one that deploys the contract. This
     * can later be changed with {transferOwnership}.
     *
     * This module is used through inheritance. It will make available the modifier
     * `onlyOwner`, which can be applied to your functions to restrict their use to
     * the owner.
     */
    abstract contract Ownable is Context {
        address private _owner;
        event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
        /**
         * @dev Initializes the contract setting the deployer as the initial owner.
         */
        constructor () internal {
            address msgSender = _msgSender();
            _owner = msgSender;
            emit OwnershipTransferred(address(0), msgSender);
        }
        /**
         * @dev Returns the address of the current owner.
         */
        function owner() public view virtual returns (address) {
            return _owner;
        }
        /**
         * @dev Throws if called by any account other than the owner.
         */
        modifier onlyOwner() {
            require(owner() == _msgSender(), "Ownable: caller is not the owner");
            _;
        }
        /**
         * @dev Leaves the contract without owner. It will not be possible to call
         * `onlyOwner` functions anymore. Can only be called by the current owner.
         *
         * NOTE: Renouncing ownership will leave the contract without an owner,
         * thereby removing any functionality that is only available to the owner.
         */
        function renounceOwnership() public virtual onlyOwner {
            emit OwnershipTransferred(_owner, address(0));
            _owner = address(0);
        }
        /**
         * @dev Transfers ownership of the contract to a new account (`newOwner`).
         * Can only be called by the current owner.
         */
        function transferOwnership(address newOwner) public virtual onlyOwner {
            require(newOwner != address(0), "Ownable: new owner is the zero address");
            emit OwnershipTransferred(_owner, newOwner);
            _owner = newOwner;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    /*
     * @dev Provides information about the current execution context, including the
     * sender of the transaction and its data. While these are generally available
     * via msg.sender and msg.data, they should not be accessed in such a direct
     * manner, since when dealing with GSN meta-transactions the account sending and
     * paying for execution may not be the actual sender (as far as an application
     * is concerned).
     *
     * This contract is only required for intermediate, library-like contracts.
     */
    abstract contract Context {
        function _msgSender() internal view virtual returns (address payable) {
            return msg.sender;
        }
        function _msgData() internal view virtual returns (bytes memory) {
            this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
            return msg.data;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    /**
     * @dev Interface of the ERC20 standard as defined in the EIP.
     */
    interface IERC20 {
        /**
         * @dev Returns the amount of tokens in existence.
         */
        function totalSupply() external view returns (uint256);
        /**
         * @dev Returns the amount of tokens owned by `account`.
         */
        function balanceOf(address account) external view returns (uint256);
        /**
         * @dev Moves `amount` tokens from the caller's account to `recipient`.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transfer(address recipient, uint256 amount) external returns (bool);
        /**
         * @dev Returns the remaining number of tokens that `spender` will be
         * allowed to spend on behalf of `owner` through {transferFrom}. This is
         * zero by default.
         *
         * This value changes when {approve} or {transferFrom} are called.
         */
        function allowance(address owner, address spender) external view returns (uint256);
        /**
         * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * IMPORTANT: Beware that changing an allowance with this method brings the risk
         * that someone may use both the old and the new allowance by unfortunate
         * transaction ordering. One possible solution to mitigate this race
         * condition is to first reduce the spender's allowance to 0 and set the
         * desired value afterwards:
         * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
         *
         * Emits an {Approval} event.
         */
        function approve(address spender, uint256 amount) external returns (bool);
        /**
         * @dev Moves `amount` tokens from `sender` to `recipient` using the
         * allowance mechanism. `amount` is then deducted from the caller's
         * allowance.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
        /**
         * @dev Emitted when `value` tokens are moved from one account (`from`) to
         * another (`to`).
         *
         * Note that `value` may be zero.
         */
        event Transfer(address indexed from, address indexed to, uint256 value);
        /**
         * @dev Emitted when the allowance of a `spender` for an `owner` is set by
         * a call to {approve}. `value` is the new allowance.
         */
        event Approval(address indexed owner, address indexed spender, uint256 value);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    /**
     * @dev Wrappers over Solidity's arithmetic operations with added overflow
     * checks.
     *
     * Arithmetic operations in Solidity wrap on overflow. This can easily result
     * in bugs, because programmers usually assume that an overflow raises an
     * error, which is the standard behavior in high level programming languages.
     * `SafeMath` restores this intuition by reverting the transaction when an
     * operation overflows.
     *
     * Using this library instead of the unchecked operations eliminates an entire
     * class of bugs, so it's recommended to use it always.
     */
    library SafeMath {
        /**
         * @dev Returns the addition of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
        /**
         * @dev Returns the substraction of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
        /**
         * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
            // benefit is lost if 'b' is also tested.
            // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
            if (a == 0) return (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
        /**
         * @dev Returns the division of two unsigned integers, with a division by zero flag.
         *
         * _Available since v3.4._
         */
        function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
         *
         * _Available since v3.4._
         */
        function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
        /**
         * @dev Returns the addition of two unsigned integers, reverting on
         * overflow.
         *
         * Counterpart to Solidity's `+` operator.
         *
         * Requirements:
         *
         * - Addition cannot overflow.
         */
        function add(uint256 a, uint256 b) internal pure returns (uint256) {
            uint256 c = a + b;
            require(c >= a, "SafeMath: addition overflow");
            return c;
        }
        /**
         * @dev Returns the subtraction of two unsigned integers, reverting on
         * overflow (when the result is negative).
         *
         * Counterpart to Solidity's `-` operator.
         *
         * Requirements:
         *
         * - Subtraction cannot overflow.
         */
        function sub(uint256 a, uint256 b) internal pure returns (uint256) {
            require(b <= a, "SafeMath: subtraction overflow");
            return a - b;
        }
        /**
         * @dev Returns the multiplication of two unsigned integers, reverting on
         * overflow.
         *
         * Counterpart to Solidity's `*` operator.
         *
         * Requirements:
         *
         * - Multiplication cannot overflow.
         */
        function mul(uint256 a, uint256 b) internal pure returns (uint256) {
            if (a == 0) return 0;
            uint256 c = a * b;
            require(c / a == b, "SafeMath: multiplication overflow");
            return c;
        }
        /**
         * @dev Returns the integer division of two unsigned integers, reverting on
         * division by zero. The result is rounded towards zero.
         *
         * Counterpart to Solidity's `/` operator. Note: this function uses a
         * `revert` opcode (which leaves remaining gas untouched) while Solidity
         * uses an invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function div(uint256 a, uint256 b) internal pure returns (uint256) {
            require(b > 0, "SafeMath: division by zero");
            return a / b;
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
         * reverting when dividing by zero.
         *
         * Counterpart to Solidity's `%` operator. This function uses a `revert`
         * opcode (which leaves remaining gas untouched) while Solidity uses an
         * invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function mod(uint256 a, uint256 b) internal pure returns (uint256) {
            require(b > 0, "SafeMath: modulo by zero");
            return a % b;
        }
        /**
         * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
         * overflow (when the result is negative).
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {trySub}.
         *
         * Counterpart to Solidity's `-` operator.
         *
         * Requirements:
         *
         * - Subtraction cannot overflow.
         */
        function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
            require(b <= a, errorMessage);
            return a - b;
        }
        /**
         * @dev Returns the integer division of two unsigned integers, reverting with custom message on
         * division by zero. The result is rounded towards zero.
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {tryDiv}.
         *
         * Counterpart to Solidity's `/` operator. Note: this function uses a
         * `revert` opcode (which leaves remaining gas untouched) while Solidity
         * uses an invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
            require(b > 0, errorMessage);
            return a / b;
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
         * reverting with custom message when dividing by zero.
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {tryMod}.
         *
         * Counterpart to Solidity's `%` operator. This function uses a `revert`
         * opcode (which leaves remaining gas untouched) while Solidity uses an
         * invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
    

    File 4 of 8: tBoneBoneDistributor
    // SPDX-License-Identifier: MIT
    pragma solidity 0.6.12;
    import "./BasicBoneDistributor.sol";
    contract tBoneBoneDistributor is BasicBoneDistributor {
        constructor (IERC20 _bone) BasicBoneDistributor(_bone) public {}
    }// SPDX-License-Identifier: MIT
    pragma solidity 0.6.12;
    import "@openzeppelin/contracts/math/SafeMath.sol";
    import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
    import "@openzeppelin/contracts/access/Ownable.sol";
    abstract contract BasicBoneDistributor is Ownable {
        using SafeMath for uint256;
        IERC20 public bone;
        bytes4 private constant SELECTOR = bytes4(keccak256(bytes('receiveApproval(address,uint256,address,uint256)')));
        uint public lockPercentage = 67;
        constructor (IERC20 _bone) public {
            require(address(_bone) != address(0), "_bone is a zero address");
            bone = _bone;
        }
        function boneBalance() external view returns(uint) {
            return bone.balanceOf(address(this));
        }
        function withdrawBone(address _destination, address _lockDestination, uint256 _lockingPeriod, uint256 _amount) external onlyOwner {
            uint256 _lockAmount = _amount.mul(lockPercentage).div(100);
            require(bone.transfer(_destination, _amount.sub(_lockAmount)), "transfer: withdraw failed");
            if(_lockAmount != 0){
                approveAndCall(_lockDestination, _lockAmount, _lockingPeriod);
            }
        }
        function approveAndCall(address _spender, uint256 _value, uint256 _lockingPeriod) internal returns (bool success) {
            bone.approve(_spender, _value);
            (bool thisSuccess,) = _spender.call(abi.encodeWithSelector(SELECTOR, bone, _value, address(this), _lockingPeriod));
            require(thisSuccess, "Spender- receiveApproval failed");
            return true;
        }
        function setLockPercentage(uint _lockPercentage) external onlyOwner {
            lockPercentage = _lockPercentage;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    /**
     * @dev Wrappers over Solidity's arithmetic operations with added overflow
     * checks.
     *
     * Arithmetic operations in Solidity wrap on overflow. This can easily result
     * in bugs, because programmers usually assume that an overflow raises an
     * error, which is the standard behavior in high level programming languages.
     * `SafeMath` restores this intuition by reverting the transaction when an
     * operation overflows.
     *
     * Using this library instead of the unchecked operations eliminates an entire
     * class of bugs, so it's recommended to use it always.
     */
    library SafeMath {
        /**
         * @dev Returns the addition of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
        /**
         * @dev Returns the substraction of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
        /**
         * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
            // benefit is lost if 'b' is also tested.
            // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
            if (a == 0) return (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
        /**
         * @dev Returns the division of two unsigned integers, with a division by zero flag.
         *
         * _Available since v3.4._
         */
        function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
         *
         * _Available since v3.4._
         */
        function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
        /**
         * @dev Returns the addition of two unsigned integers, reverting on
         * overflow.
         *
         * Counterpart to Solidity's `+` operator.
         *
         * Requirements:
         *
         * - Addition cannot overflow.
         */
        function add(uint256 a, uint256 b) internal pure returns (uint256) {
            uint256 c = a + b;
            require(c >= a, "SafeMath: addition overflow");
            return c;
        }
        /**
         * @dev Returns the subtraction of two unsigned integers, reverting on
         * overflow (when the result is negative).
         *
         * Counterpart to Solidity's `-` operator.
         *
         * Requirements:
         *
         * - Subtraction cannot overflow.
         */
        function sub(uint256 a, uint256 b) internal pure returns (uint256) {
            require(b <= a, "SafeMath: subtraction overflow");
            return a - b;
        }
        /**
         * @dev Returns the multiplication of two unsigned integers, reverting on
         * overflow.
         *
         * Counterpart to Solidity's `*` operator.
         *
         * Requirements:
         *
         * - Multiplication cannot overflow.
         */
        function mul(uint256 a, uint256 b) internal pure returns (uint256) {
            if (a == 0) return 0;
            uint256 c = a * b;
            require(c / a == b, "SafeMath: multiplication overflow");
            return c;
        }
        /**
         * @dev Returns the integer division of two unsigned integers, reverting on
         * division by zero. The result is rounded towards zero.
         *
         * Counterpart to Solidity's `/` operator. Note: this function uses a
         * `revert` opcode (which leaves remaining gas untouched) while Solidity
         * uses an invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function div(uint256 a, uint256 b) internal pure returns (uint256) {
            require(b > 0, "SafeMath: division by zero");
            return a / b;
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
         * reverting when dividing by zero.
         *
         * Counterpart to Solidity's `%` operator. This function uses a `revert`
         * opcode (which leaves remaining gas untouched) while Solidity uses an
         * invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function mod(uint256 a, uint256 b) internal pure returns (uint256) {
            require(b > 0, "SafeMath: modulo by zero");
            return a % b;
        }
        /**
         * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
         * overflow (when the result is negative).
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {trySub}.
         *
         * Counterpart to Solidity's `-` operator.
         *
         * Requirements:
         *
         * - Subtraction cannot overflow.
         */
        function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
            require(b <= a, errorMessage);
            return a - b;
        }
        /**
         * @dev Returns the integer division of two unsigned integers, reverting with custom message on
         * division by zero. The result is rounded towards zero.
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {tryDiv}.
         *
         * Counterpart to Solidity's `/` operator. Note: this function uses a
         * `revert` opcode (which leaves remaining gas untouched) while Solidity
         * uses an invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
            require(b > 0, errorMessage);
            return a / b;
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
         * reverting with custom message when dividing by zero.
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {tryMod}.
         *
         * Counterpart to Solidity's `%` operator. This function uses a `revert`
         * opcode (which leaves remaining gas untouched) while Solidity uses an
         * invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    /**
     * @dev Interface of the ERC20 standard as defined in the EIP.
     */
    interface IERC20 {
        /**
         * @dev Returns the amount of tokens in existence.
         */
        function totalSupply() external view returns (uint256);
        /**
         * @dev Returns the amount of tokens owned by `account`.
         */
        function balanceOf(address account) external view returns (uint256);
        /**
         * @dev Moves `amount` tokens from the caller's account to `recipient`.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transfer(address recipient, uint256 amount) external returns (bool);
        /**
         * @dev Returns the remaining number of tokens that `spender` will be
         * allowed to spend on behalf of `owner` through {transferFrom}. This is
         * zero by default.
         *
         * This value changes when {approve} or {transferFrom} are called.
         */
        function allowance(address owner, address spender) external view returns (uint256);
        /**
         * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * IMPORTANT: Beware that changing an allowance with this method brings the risk
         * that someone may use both the old and the new allowance by unfortunate
         * transaction ordering. One possible solution to mitigate this race
         * condition is to first reduce the spender's allowance to 0 and set the
         * desired value afterwards:
         * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
         *
         * Emits an {Approval} event.
         */
        function approve(address spender, uint256 amount) external returns (bool);
        /**
         * @dev Moves `amount` tokens from `sender` to `recipient` using the
         * allowance mechanism. `amount` is then deducted from the caller's
         * allowance.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
        /**
         * @dev Emitted when `value` tokens are moved from one account (`from`) to
         * another (`to`).
         *
         * Note that `value` may be zero.
         */
        event Transfer(address indexed from, address indexed to, uint256 value);
        /**
         * @dev Emitted when the allowance of a `spender` for an `owner` is set by
         * a call to {approve}. `value` is the new allowance.
         */
        event Approval(address indexed owner, address indexed spender, uint256 value);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    import "../utils/Context.sol";
    /**
     * @dev Contract module which provides a basic access control mechanism, where
     * there is an account (an owner) that can be granted exclusive access to
     * specific functions.
     *
     * By default, the owner account will be the one that deploys the contract. This
     * can later be changed with {transferOwnership}.
     *
     * This module is used through inheritance. It will make available the modifier
     * `onlyOwner`, which can be applied to your functions to restrict their use to
     * the owner.
     */
    abstract contract Ownable is Context {
        address private _owner;
        event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
        /**
         * @dev Initializes the contract setting the deployer as the initial owner.
         */
        constructor () internal {
            address msgSender = _msgSender();
            _owner = msgSender;
            emit OwnershipTransferred(address(0), msgSender);
        }
        /**
         * @dev Returns the address of the current owner.
         */
        function owner() public view virtual returns (address) {
            return _owner;
        }
        /**
         * @dev Throws if called by any account other than the owner.
         */
        modifier onlyOwner() {
            require(owner() == _msgSender(), "Ownable: caller is not the owner");
            _;
        }
        /**
         * @dev Leaves the contract without owner. It will not be possible to call
         * `onlyOwner` functions anymore. Can only be called by the current owner.
         *
         * NOTE: Renouncing ownership will leave the contract without an owner,
         * thereby removing any functionality that is only available to the owner.
         */
        function renounceOwnership() public virtual onlyOwner {
            emit OwnershipTransferred(_owner, address(0));
            _owner = address(0);
        }
        /**
         * @dev Transfers ownership of the contract to a new account (`newOwner`).
         * Can only be called by the current owner.
         */
        function transferOwnership(address newOwner) public virtual onlyOwner {
            require(newOwner != address(0), "Ownable: new owner is the zero address");
            emit OwnershipTransferred(_owner, newOwner);
            _owner = newOwner;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    /*
     * @dev Provides information about the current execution context, including the
     * sender of the transaction and its data. While these are generally available
     * via msg.sender and msg.data, they should not be accessed in such a direct
     * manner, since when dealing with GSN meta-transactions the account sending and
     * paying for execution may not be the actual sender (as far as an application
     * is concerned).
     *
     * This contract is only required for intermediate, library-like contracts.
     */
    abstract contract Context {
        function _msgSender() internal view virtual returns (address payable) {
            return msg.sender;
        }
        function _msgData() internal view virtual returns (bytes memory) {
            this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
            return msg.data;
        }
    }
    

    File 5 of 8: xShibBoneDistributor
    // SPDX-License-Identifier: MIT
    pragma solidity 0.6.12;
    import "./BasicBoneDistributor.sol";
    contract xShibBoneDistributor is BasicBoneDistributor {
        constructor (IERC20 _bone) BasicBoneDistributor(_bone) public {}
    }// SPDX-License-Identifier: MIT
    pragma solidity 0.6.12;
    import "@openzeppelin/contracts/math/SafeMath.sol";
    import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
    import "@openzeppelin/contracts/access/Ownable.sol";
    abstract contract BasicBoneDistributor is Ownable {
        using SafeMath for uint256;
        IERC20 public bone;
        bytes4 private constant SELECTOR = bytes4(keccak256(bytes('receiveApproval(address,uint256,address,uint256)')));
        uint public lockPercentage = 67;
        constructor (IERC20 _bone) public {
            require(address(_bone) != address(0), "_bone is a zero address");
            bone = _bone;
        }
        function boneBalance() external view returns(uint) {
            return bone.balanceOf(address(this));
        }
        function withdrawBone(address _destination, address _lockDestination, uint256 _lockingPeriod, uint256 _amount) external onlyOwner {
            uint256 _lockAmount = _amount.mul(lockPercentage).div(100);
            require(bone.transfer(_destination, _amount.sub(_lockAmount)), "transfer: withdraw failed");
            if(_lockAmount != 0){
                approveAndCall(_lockDestination, _lockAmount, _lockingPeriod);
            }
        }
        function approveAndCall(address _spender, uint256 _value, uint256 _lockingPeriod) internal returns (bool success) {
            bone.approve(_spender, _value);
            (bool thisSuccess,) = _spender.call(abi.encodeWithSelector(SELECTOR, bone, _value, address(this), _lockingPeriod));
            require(thisSuccess, "Spender- receiveApproval failed");
            return true;
        }
        function setLockPercentage(uint _lockPercentage) external onlyOwner {
            lockPercentage = _lockPercentage;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    /**
     * @dev Wrappers over Solidity's arithmetic operations with added overflow
     * checks.
     *
     * Arithmetic operations in Solidity wrap on overflow. This can easily result
     * in bugs, because programmers usually assume that an overflow raises an
     * error, which is the standard behavior in high level programming languages.
     * `SafeMath` restores this intuition by reverting the transaction when an
     * operation overflows.
     *
     * Using this library instead of the unchecked operations eliminates an entire
     * class of bugs, so it's recommended to use it always.
     */
    library SafeMath {
        /**
         * @dev Returns the addition of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
        /**
         * @dev Returns the substraction of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
        /**
         * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
            // benefit is lost if 'b' is also tested.
            // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
            if (a == 0) return (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
        /**
         * @dev Returns the division of two unsigned integers, with a division by zero flag.
         *
         * _Available since v3.4._
         */
        function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
         *
         * _Available since v3.4._
         */
        function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
        /**
         * @dev Returns the addition of two unsigned integers, reverting on
         * overflow.
         *
         * Counterpart to Solidity's `+` operator.
         *
         * Requirements:
         *
         * - Addition cannot overflow.
         */
        function add(uint256 a, uint256 b) internal pure returns (uint256) {
            uint256 c = a + b;
            require(c >= a, "SafeMath: addition overflow");
            return c;
        }
        /**
         * @dev Returns the subtraction of two unsigned integers, reverting on
         * overflow (when the result is negative).
         *
         * Counterpart to Solidity's `-` operator.
         *
         * Requirements:
         *
         * - Subtraction cannot overflow.
         */
        function sub(uint256 a, uint256 b) internal pure returns (uint256) {
            require(b <= a, "SafeMath: subtraction overflow");
            return a - b;
        }
        /**
         * @dev Returns the multiplication of two unsigned integers, reverting on
         * overflow.
         *
         * Counterpart to Solidity's `*` operator.
         *
         * Requirements:
         *
         * - Multiplication cannot overflow.
         */
        function mul(uint256 a, uint256 b) internal pure returns (uint256) {
            if (a == 0) return 0;
            uint256 c = a * b;
            require(c / a == b, "SafeMath: multiplication overflow");
            return c;
        }
        /**
         * @dev Returns the integer division of two unsigned integers, reverting on
         * division by zero. The result is rounded towards zero.
         *
         * Counterpart to Solidity's `/` operator. Note: this function uses a
         * `revert` opcode (which leaves remaining gas untouched) while Solidity
         * uses an invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function div(uint256 a, uint256 b) internal pure returns (uint256) {
            require(b > 0, "SafeMath: division by zero");
            return a / b;
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
         * reverting when dividing by zero.
         *
         * Counterpart to Solidity's `%` operator. This function uses a `revert`
         * opcode (which leaves remaining gas untouched) while Solidity uses an
         * invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function mod(uint256 a, uint256 b) internal pure returns (uint256) {
            require(b > 0, "SafeMath: modulo by zero");
            return a % b;
        }
        /**
         * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
         * overflow (when the result is negative).
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {trySub}.
         *
         * Counterpart to Solidity's `-` operator.
         *
         * Requirements:
         *
         * - Subtraction cannot overflow.
         */
        function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
            require(b <= a, errorMessage);
            return a - b;
        }
        /**
         * @dev Returns the integer division of two unsigned integers, reverting with custom message on
         * division by zero. The result is rounded towards zero.
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {tryDiv}.
         *
         * Counterpart to Solidity's `/` operator. Note: this function uses a
         * `revert` opcode (which leaves remaining gas untouched) while Solidity
         * uses an invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
            require(b > 0, errorMessage);
            return a / b;
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
         * reverting with custom message when dividing by zero.
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {tryMod}.
         *
         * Counterpart to Solidity's `%` operator. This function uses a `revert`
         * opcode (which leaves remaining gas untouched) while Solidity uses an
         * invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    /**
     * @dev Interface of the ERC20 standard as defined in the EIP.
     */
    interface IERC20 {
        /**
         * @dev Returns the amount of tokens in existence.
         */
        function totalSupply() external view returns (uint256);
        /**
         * @dev Returns the amount of tokens owned by `account`.
         */
        function balanceOf(address account) external view returns (uint256);
        /**
         * @dev Moves `amount` tokens from the caller's account to `recipient`.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transfer(address recipient, uint256 amount) external returns (bool);
        /**
         * @dev Returns the remaining number of tokens that `spender` will be
         * allowed to spend on behalf of `owner` through {transferFrom}. This is
         * zero by default.
         *
         * This value changes when {approve} or {transferFrom} are called.
         */
        function allowance(address owner, address spender) external view returns (uint256);
        /**
         * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * IMPORTANT: Beware that changing an allowance with this method brings the risk
         * that someone may use both the old and the new allowance by unfortunate
         * transaction ordering. One possible solution to mitigate this race
         * condition is to first reduce the spender's allowance to 0 and set the
         * desired value afterwards:
         * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
         *
         * Emits an {Approval} event.
         */
        function approve(address spender, uint256 amount) external returns (bool);
        /**
         * @dev Moves `amount` tokens from `sender` to `recipient` using the
         * allowance mechanism. `amount` is then deducted from the caller's
         * allowance.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
        /**
         * @dev Emitted when `value` tokens are moved from one account (`from`) to
         * another (`to`).
         *
         * Note that `value` may be zero.
         */
        event Transfer(address indexed from, address indexed to, uint256 value);
        /**
         * @dev Emitted when the allowance of a `spender` for an `owner` is set by
         * a call to {approve}. `value` is the new allowance.
         */
        event Approval(address indexed owner, address indexed spender, uint256 value);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    import "../utils/Context.sol";
    /**
     * @dev Contract module which provides a basic access control mechanism, where
     * there is an account (an owner) that can be granted exclusive access to
     * specific functions.
     *
     * By default, the owner account will be the one that deploys the contract. This
     * can later be changed with {transferOwnership}.
     *
     * This module is used through inheritance. It will make available the modifier
     * `onlyOwner`, which can be applied to your functions to restrict their use to
     * the owner.
     */
    abstract contract Ownable is Context {
        address private _owner;
        event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
        /**
         * @dev Initializes the contract setting the deployer as the initial owner.
         */
        constructor () internal {
            address msgSender = _msgSender();
            _owner = msgSender;
            emit OwnershipTransferred(address(0), msgSender);
        }
        /**
         * @dev Returns the address of the current owner.
         */
        function owner() public view virtual returns (address) {
            return _owner;
        }
        /**
         * @dev Throws if called by any account other than the owner.
         */
        modifier onlyOwner() {
            require(owner() == _msgSender(), "Ownable: caller is not the owner");
            _;
        }
        /**
         * @dev Leaves the contract without owner. It will not be possible to call
         * `onlyOwner` functions anymore. Can only be called by the current owner.
         *
         * NOTE: Renouncing ownership will leave the contract without an owner,
         * thereby removing any functionality that is only available to the owner.
         */
        function renounceOwnership() public virtual onlyOwner {
            emit OwnershipTransferred(_owner, address(0));
            _owner = address(0);
        }
        /**
         * @dev Transfers ownership of the contract to a new account (`newOwner`).
         * Can only be called by the current owner.
         */
        function transferOwnership(address newOwner) public virtual onlyOwner {
            require(newOwner != address(0), "Ownable: new owner is the zero address");
            emit OwnershipTransferred(_owner, newOwner);
            _owner = newOwner;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    /*
     * @dev Provides information about the current execution context, including the
     * sender of the transaction and its data. While these are generally available
     * via msg.sender and msg.data, they should not be accessed in such a direct
     * manner, since when dealing with GSN meta-transactions the account sending and
     * paying for execution may not be the actual sender (as far as an application
     * is concerned).
     *
     * This contract is only required for intermediate, library-like contracts.
     */
    abstract contract Context {
        function _msgSender() internal view virtual returns (address payable) {
            return msg.sender;
        }
        function _msgData() internal view virtual returns (bytes memory) {
            this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
            return msg.data;
        }
    }
    

    File 6 of 8: xLeashBoneDistributor
    // SPDX-License-Identifier: MIT
    pragma solidity 0.6.12;
    import "./BasicBoneDistributor.sol";
    contract xLeashBoneDistributor is BasicBoneDistributor {
        constructor (IERC20 _bone) BasicBoneDistributor(_bone) public {}
    }// SPDX-License-Identifier: MIT
    pragma solidity 0.6.12;
    import "@openzeppelin/contracts/math/SafeMath.sol";
    import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
    import "@openzeppelin/contracts/access/Ownable.sol";
    abstract contract BasicBoneDistributor is Ownable {
        using SafeMath for uint256;
        IERC20 public bone;
        bytes4 private constant SELECTOR = bytes4(keccak256(bytes('receiveApproval(address,uint256,address,uint256)')));
        uint public lockPercentage = 67;
        constructor (IERC20 _bone) public {
            require(address(_bone) != address(0), "_bone is a zero address");
            bone = _bone;
        }
        function boneBalance() external view returns(uint) {
            return bone.balanceOf(address(this));
        }
        function withdrawBone(address _destination, address _lockDestination, uint256 _lockingPeriod, uint256 _amount) external onlyOwner {
            uint256 _lockAmount = _amount.mul(lockPercentage).div(100);
            require(bone.transfer(_destination, _amount.sub(_lockAmount)), "transfer: withdraw failed");
            if(_lockAmount != 0){
                approveAndCall(_lockDestination, _lockAmount, _lockingPeriod);
            }
        }
        function approveAndCall(address _spender, uint256 _value, uint256 _lockingPeriod) internal returns (bool success) {
            bone.approve(_spender, _value);
            (bool thisSuccess,) = _spender.call(abi.encodeWithSelector(SELECTOR, bone, _value, address(this), _lockingPeriod));
            require(thisSuccess, "Spender- receiveApproval failed");
            return true;
        }
        function setLockPercentage(uint _lockPercentage) external onlyOwner {
            lockPercentage = _lockPercentage;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    /**
     * @dev Wrappers over Solidity's arithmetic operations with added overflow
     * checks.
     *
     * Arithmetic operations in Solidity wrap on overflow. This can easily result
     * in bugs, because programmers usually assume that an overflow raises an
     * error, which is the standard behavior in high level programming languages.
     * `SafeMath` restores this intuition by reverting the transaction when an
     * operation overflows.
     *
     * Using this library instead of the unchecked operations eliminates an entire
     * class of bugs, so it's recommended to use it always.
     */
    library SafeMath {
        /**
         * @dev Returns the addition of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
        /**
         * @dev Returns the substraction of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
        /**
         * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
            // benefit is lost if 'b' is also tested.
            // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
            if (a == 0) return (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
        /**
         * @dev Returns the division of two unsigned integers, with a division by zero flag.
         *
         * _Available since v3.4._
         */
        function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
         *
         * _Available since v3.4._
         */
        function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
        /**
         * @dev Returns the addition of two unsigned integers, reverting on
         * overflow.
         *
         * Counterpart to Solidity's `+` operator.
         *
         * Requirements:
         *
         * - Addition cannot overflow.
         */
        function add(uint256 a, uint256 b) internal pure returns (uint256) {
            uint256 c = a + b;
            require(c >= a, "SafeMath: addition overflow");
            return c;
        }
        /**
         * @dev Returns the subtraction of two unsigned integers, reverting on
         * overflow (when the result is negative).
         *
         * Counterpart to Solidity's `-` operator.
         *
         * Requirements:
         *
         * - Subtraction cannot overflow.
         */
        function sub(uint256 a, uint256 b) internal pure returns (uint256) {
            require(b <= a, "SafeMath: subtraction overflow");
            return a - b;
        }
        /**
         * @dev Returns the multiplication of two unsigned integers, reverting on
         * overflow.
         *
         * Counterpart to Solidity's `*` operator.
         *
         * Requirements:
         *
         * - Multiplication cannot overflow.
         */
        function mul(uint256 a, uint256 b) internal pure returns (uint256) {
            if (a == 0) return 0;
            uint256 c = a * b;
            require(c / a == b, "SafeMath: multiplication overflow");
            return c;
        }
        /**
         * @dev Returns the integer division of two unsigned integers, reverting on
         * division by zero. The result is rounded towards zero.
         *
         * Counterpart to Solidity's `/` operator. Note: this function uses a
         * `revert` opcode (which leaves remaining gas untouched) while Solidity
         * uses an invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function div(uint256 a, uint256 b) internal pure returns (uint256) {
            require(b > 0, "SafeMath: division by zero");
            return a / b;
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
         * reverting when dividing by zero.
         *
         * Counterpart to Solidity's `%` operator. This function uses a `revert`
         * opcode (which leaves remaining gas untouched) while Solidity uses an
         * invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function mod(uint256 a, uint256 b) internal pure returns (uint256) {
            require(b > 0, "SafeMath: modulo by zero");
            return a % b;
        }
        /**
         * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
         * overflow (when the result is negative).
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {trySub}.
         *
         * Counterpart to Solidity's `-` operator.
         *
         * Requirements:
         *
         * - Subtraction cannot overflow.
         */
        function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
            require(b <= a, errorMessage);
            return a - b;
        }
        /**
         * @dev Returns the integer division of two unsigned integers, reverting with custom message on
         * division by zero. The result is rounded towards zero.
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {tryDiv}.
         *
         * Counterpart to Solidity's `/` operator. Note: this function uses a
         * `revert` opcode (which leaves remaining gas untouched) while Solidity
         * uses an invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
            require(b > 0, errorMessage);
            return a / b;
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
         * reverting with custom message when dividing by zero.
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {tryMod}.
         *
         * Counterpart to Solidity's `%` operator. This function uses a `revert`
         * opcode (which leaves remaining gas untouched) while Solidity uses an
         * invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    /**
     * @dev Interface of the ERC20 standard as defined in the EIP.
     */
    interface IERC20 {
        /**
         * @dev Returns the amount of tokens in existence.
         */
        function totalSupply() external view returns (uint256);
        /**
         * @dev Returns the amount of tokens owned by `account`.
         */
        function balanceOf(address account) external view returns (uint256);
        /**
         * @dev Moves `amount` tokens from the caller's account to `recipient`.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transfer(address recipient, uint256 amount) external returns (bool);
        /**
         * @dev Returns the remaining number of tokens that `spender` will be
         * allowed to spend on behalf of `owner` through {transferFrom}. This is
         * zero by default.
         *
         * This value changes when {approve} or {transferFrom} are called.
         */
        function allowance(address owner, address spender) external view returns (uint256);
        /**
         * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * IMPORTANT: Beware that changing an allowance with this method brings the risk
         * that someone may use both the old and the new allowance by unfortunate
         * transaction ordering. One possible solution to mitigate this race
         * condition is to first reduce the spender's allowance to 0 and set the
         * desired value afterwards:
         * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
         *
         * Emits an {Approval} event.
         */
        function approve(address spender, uint256 amount) external returns (bool);
        /**
         * @dev Moves `amount` tokens from `sender` to `recipient` using the
         * allowance mechanism. `amount` is then deducted from the caller's
         * allowance.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
        /**
         * @dev Emitted when `value` tokens are moved from one account (`from`) to
         * another (`to`).
         *
         * Note that `value` may be zero.
         */
        event Transfer(address indexed from, address indexed to, uint256 value);
        /**
         * @dev Emitted when the allowance of a `spender` for an `owner` is set by
         * a call to {approve}. `value` is the new allowance.
         */
        event Approval(address indexed owner, address indexed spender, uint256 value);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    import "../utils/Context.sol";
    /**
     * @dev Contract module which provides a basic access control mechanism, where
     * there is an account (an owner) that can be granted exclusive access to
     * specific functions.
     *
     * By default, the owner account will be the one that deploys the contract. This
     * can later be changed with {transferOwnership}.
     *
     * This module is used through inheritance. It will make available the modifier
     * `onlyOwner`, which can be applied to your functions to restrict their use to
     * the owner.
     */
    abstract contract Ownable is Context {
        address private _owner;
        event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
        /**
         * @dev Initializes the contract setting the deployer as the initial owner.
         */
        constructor () internal {
            address msgSender = _msgSender();
            _owner = msgSender;
            emit OwnershipTransferred(address(0), msgSender);
        }
        /**
         * @dev Returns the address of the current owner.
         */
        function owner() public view virtual returns (address) {
            return _owner;
        }
        /**
         * @dev Throws if called by any account other than the owner.
         */
        modifier onlyOwner() {
            require(owner() == _msgSender(), "Ownable: caller is not the owner");
            _;
        }
        /**
         * @dev Leaves the contract without owner. It will not be possible to call
         * `onlyOwner` functions anymore. Can only be called by the current owner.
         *
         * NOTE: Renouncing ownership will leave the contract without an owner,
         * thereby removing any functionality that is only available to the owner.
         */
        function renounceOwnership() public virtual onlyOwner {
            emit OwnershipTransferred(_owner, address(0));
            _owner = address(0);
        }
        /**
         * @dev Transfers ownership of the contract to a new account (`newOwner`).
         * Can only be called by the current owner.
         */
        function transferOwnership(address newOwner) public virtual onlyOwner {
            require(newOwner != address(0), "Ownable: new owner is the zero address");
            emit OwnershipTransferred(_owner, newOwner);
            _owner = newOwner;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    /*
     * @dev Provides information about the current execution context, including the
     * sender of the transaction and its data. While these are generally available
     * via msg.sender and msg.data, they should not be accessed in such a direct
     * manner, since when dealing with GSN meta-transactions the account sending and
     * paying for execution may not be the actual sender (as far as an application
     * is concerned).
     *
     * This contract is only required for intermediate, library-like contracts.
     */
    abstract contract Context {
        function _msgSender() internal view virtual returns (address payable) {
            return msg.sender;
        }
        function _msgData() internal view virtual returns (bytes memory) {
            this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
            return msg.data;
        }
    }
    

    File 7 of 8: BoneLocker
    // SPDX-License-Identifier: UNLICENSED
    pragma solidity 0.6.12;
    import "@openzeppelin/contracts/access/Ownable.sol";
    import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
    import "@openzeppelin/contracts/math/SafeMath.sol";
    // BoneToken locker contract.
    contract BoneLocker is Ownable {
        using SafeMath for uint256;
        IERC20 boneToken;
        address emergencyAddress;
        bool emergencyFlag = false;
        struct LockInfo{
            uint256 _amount;
            uint256 _timestamp;
            bool _isDev;
        }
        uint256 public lockingPeriod;
        uint256 public devLockingPeriod;
        mapping (address => LockInfo[]) public lockInfoByUser;
        mapping (address => uint256) public latestCounterByUser;
        mapping (address => uint256) public unclaimedTokensByUser;
        event LockingPeriod(address indexed user, uint newLockingPeriod, uint newDevLockingPeriod);
        constructor(address _boneToken, address _emergencyAddress, uint256 _lockingPeriodInDays, uint256 _devLockingPeriodInDays) public {
            require(address(_boneToken) != address(0), "_bone token is a zero address");
            require(address(_emergencyAddress) != address(0), "_emergencyAddress is a zero address");
            boneToken = IERC20(_boneToken);
            emergencyAddress = _emergencyAddress;
            lockingPeriod = _lockingPeriodInDays * 1 days;
            devLockingPeriod = _devLockingPeriodInDays * 1 days;
        }
        // function to lock user reward bone tokens in token contract, called by onlyOwner that would be TopDog.sol
        function lock(address _holder, uint256 _amount, bool _isDev) external onlyOwner {
            require(_holder != address(0), "Invalid user address");
            require(_amount > 0, "Invalid amount entered");
            lockInfoByUser[_holder].push(LockInfo(_amount, now, _isDev));
            unclaimedTokensByUser[_holder] = unclaimedTokensByUser[_holder].add(_amount);
        }
        // function to claim all the tokens locked for a user, after the locking period
        function claimAllForUser(uint256 r, address user) public {
            require(!emergencyFlag, "Emergency mode, cannot access this function");
            require(r>latestCounterByUser[user], "Increase right header, already claimed till this");
            require(r<=lockInfoByUser[user].length, "Decrease right header, it exceeds total length");
            LockInfo[] memory lockInfoArrayForUser = lockInfoByUser[user];
            uint256 totalTransferableAmount = 0;
            uint i;
            for (i=latestCounterByUser[user]; i<r; i++){
                uint256 lockingPeriodHere = lockingPeriod;
                if(lockInfoArrayForUser[i]._isDev){
                    lockingPeriodHere = devLockingPeriod;
                }
                if(now >= (lockInfoArrayForUser[i]._timestamp.add(lockingPeriodHere))){
                    totalTransferableAmount = totalTransferableAmount.add(lockInfoArrayForUser[i]._amount);
                    unclaimedTokensByUser[user] = unclaimedTokensByUser[user].sub(lockInfoArrayForUser[i]._amount);
                    latestCounterByUser[user] = i.add(1);
                } else {
                    break;
                }
            }
            boneToken.transfer(user, totalTransferableAmount);
        }
        // function to claim all the tokens locked by user, after the locking period
        function claimAll(uint256 r) external {
            claimAllForUser(r, msg.sender);
        }
        // function to get claimable amount for any user
        function getClaimableAmount(address _user) external view returns(uint256) {
            LockInfo[] memory lockInfoArrayForUser = lockInfoByUser[_user];
            uint256 totalTransferableAmount = 0;
            uint i;
            for (i=latestCounterByUser[_user]; i<lockInfoArrayForUser.length; i++){
                uint256 lockingPeriodHere = lockingPeriod;
                if(lockInfoArrayForUser[i]._isDev){
                    lockingPeriodHere = devLockingPeriod;
                }
                if(now >= (lockInfoArrayForUser[i]._timestamp.add(lockingPeriodHere))){
                    totalTransferableAmount = totalTransferableAmount.add(lockInfoArrayForUser[i]._amount);
                } else {
                    break;
                }
            }
            return totalTransferableAmount;
        }
        // get the left and right headers for a user, left header is the index counter till which we have already iterated, right header is basically the length of user's lockInfo array
        function getLeftRightCounters(address _user) external view returns(uint256, uint256){
            return(latestCounterByUser[_user], lockInfoByUser[_user].length);
        }
        // in cases of emergency, emergency address can set this to true, which will enable emergencyWithdraw function
        function setEmergencyFlag(bool _emergencyFlag) external {
            require(msg.sender == emergencyAddress, "This function can only be called by emergencyAddress");
            emergencyFlag = _emergencyFlag;
        }
        // function for owner to transfer all tokens to another address
        function emergencyWithdrawOwner(address _to) external onlyOwner{
            uint256 amount = boneToken.balanceOf(address(this));
            require(boneToken.transfer(_to, amount), 'MerkleDistributor: Transfer failed.');
        }
        // emergency address can be updated from here
        function setEmergencyAddr(address _newAddr) external {
            require(msg.sender == emergencyAddress, "This function can only be called by emergencyAddress");
            require(_newAddr != address(0), "_newAddr is a zero address");
            emergencyAddress = _newAddr;
        }
        // function to update/change the normal & dev locking period
        function setLockingPeriod(uint256 _newLockingPeriod, uint256 _newDevLockingPeriod) external onlyOwner {
            lockingPeriod = _newLockingPeriod;
            devLockingPeriod = _newDevLockingPeriod;
            emit LockingPeriod(msg.sender, _newLockingPeriod, _newDevLockingPeriod);
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    import "../utils/Context.sol";
    /**
     * @dev Contract module which provides a basic access control mechanism, where
     * there is an account (an owner) that can be granted exclusive access to
     * specific functions.
     *
     * By default, the owner account will be the one that deploys the contract. This
     * can later be changed with {transferOwnership}.
     *
     * This module is used through inheritance. It will make available the modifier
     * `onlyOwner`, which can be applied to your functions to restrict their use to
     * the owner.
     */
    abstract contract Ownable is Context {
        address private _owner;
        event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
        /**
         * @dev Initializes the contract setting the deployer as the initial owner.
         */
        constructor () internal {
            address msgSender = _msgSender();
            _owner = msgSender;
            emit OwnershipTransferred(address(0), msgSender);
        }
        /**
         * @dev Returns the address of the current owner.
         */
        function owner() public view virtual returns (address) {
            return _owner;
        }
        /**
         * @dev Throws if called by any account other than the owner.
         */
        modifier onlyOwner() {
            require(owner() == _msgSender(), "Ownable: caller is not the owner");
            _;
        }
        /**
         * @dev Leaves the contract without owner. It will not be possible to call
         * `onlyOwner` functions anymore. Can only be called by the current owner.
         *
         * NOTE: Renouncing ownership will leave the contract without an owner,
         * thereby removing any functionality that is only available to the owner.
         */
        function renounceOwnership() public virtual onlyOwner {
            emit OwnershipTransferred(_owner, address(0));
            _owner = address(0);
        }
        /**
         * @dev Transfers ownership of the contract to a new account (`newOwner`).
         * Can only be called by the current owner.
         */
        function transferOwnership(address newOwner) public virtual onlyOwner {
            require(newOwner != address(0), "Ownable: new owner is the zero address");
            emit OwnershipTransferred(_owner, newOwner);
            _owner = newOwner;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    /**
     * @dev Interface of the ERC20 standard as defined in the EIP.
     */
    interface IERC20 {
        /**
         * @dev Returns the amount of tokens in existence.
         */
        function totalSupply() external view returns (uint256);
        /**
         * @dev Returns the amount of tokens owned by `account`.
         */
        function balanceOf(address account) external view returns (uint256);
        /**
         * @dev Moves `amount` tokens from the caller's account to `recipient`.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transfer(address recipient, uint256 amount) external returns (bool);
        /**
         * @dev Returns the remaining number of tokens that `spender` will be
         * allowed to spend on behalf of `owner` through {transferFrom}. This is
         * zero by default.
         *
         * This value changes when {approve} or {transferFrom} are called.
         */
        function allowance(address owner, address spender) external view returns (uint256);
        /**
         * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * IMPORTANT: Beware that changing an allowance with this method brings the risk
         * that someone may use both the old and the new allowance by unfortunate
         * transaction ordering. One possible solution to mitigate this race
         * condition is to first reduce the spender's allowance to 0 and set the
         * desired value afterwards:
         * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
         *
         * Emits an {Approval} event.
         */
        function approve(address spender, uint256 amount) external returns (bool);
        /**
         * @dev Moves `amount` tokens from `sender` to `recipient` using the
         * allowance mechanism. `amount` is then deducted from the caller's
         * allowance.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
        /**
         * @dev Emitted when `value` tokens are moved from one account (`from`) to
         * another (`to`).
         *
         * Note that `value` may be zero.
         */
        event Transfer(address indexed from, address indexed to, uint256 value);
        /**
         * @dev Emitted when the allowance of a `spender` for an `owner` is set by
         * a call to {approve}. `value` is the new allowance.
         */
        event Approval(address indexed owner, address indexed spender, uint256 value);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    /**
     * @dev Wrappers over Solidity's arithmetic operations with added overflow
     * checks.
     *
     * Arithmetic operations in Solidity wrap on overflow. This can easily result
     * in bugs, because programmers usually assume that an overflow raises an
     * error, which is the standard behavior in high level programming languages.
     * `SafeMath` restores this intuition by reverting the transaction when an
     * operation overflows.
     *
     * Using this library instead of the unchecked operations eliminates an entire
     * class of bugs, so it's recommended to use it always.
     */
    library SafeMath {
        /**
         * @dev Returns the addition of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
        /**
         * @dev Returns the substraction of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
        /**
         * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
            // benefit is lost if 'b' is also tested.
            // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
            if (a == 0) return (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
        /**
         * @dev Returns the division of two unsigned integers, with a division by zero flag.
         *
         * _Available since v3.4._
         */
        function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
         *
         * _Available since v3.4._
         */
        function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
        /**
         * @dev Returns the addition of two unsigned integers, reverting on
         * overflow.
         *
         * Counterpart to Solidity's `+` operator.
         *
         * Requirements:
         *
         * - Addition cannot overflow.
         */
        function add(uint256 a, uint256 b) internal pure returns (uint256) {
            uint256 c = a + b;
            require(c >= a, "SafeMath: addition overflow");
            return c;
        }
        /**
         * @dev Returns the subtraction of two unsigned integers, reverting on
         * overflow (when the result is negative).
         *
         * Counterpart to Solidity's `-` operator.
         *
         * Requirements:
         *
         * - Subtraction cannot overflow.
         */
        function sub(uint256 a, uint256 b) internal pure returns (uint256) {
            require(b <= a, "SafeMath: subtraction overflow");
            return a - b;
        }
        /**
         * @dev Returns the multiplication of two unsigned integers, reverting on
         * overflow.
         *
         * Counterpart to Solidity's `*` operator.
         *
         * Requirements:
         *
         * - Multiplication cannot overflow.
         */
        function mul(uint256 a, uint256 b) internal pure returns (uint256) {
            if (a == 0) return 0;
            uint256 c = a * b;
            require(c / a == b, "SafeMath: multiplication overflow");
            return c;
        }
        /**
         * @dev Returns the integer division of two unsigned integers, reverting on
         * division by zero. The result is rounded towards zero.
         *
         * Counterpart to Solidity's `/` operator. Note: this function uses a
         * `revert` opcode (which leaves remaining gas untouched) while Solidity
         * uses an invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function div(uint256 a, uint256 b) internal pure returns (uint256) {
            require(b > 0, "SafeMath: division by zero");
            return a / b;
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
         * reverting when dividing by zero.
         *
         * Counterpart to Solidity's `%` operator. This function uses a `revert`
         * opcode (which leaves remaining gas untouched) while Solidity uses an
         * invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function mod(uint256 a, uint256 b) internal pure returns (uint256) {
            require(b > 0, "SafeMath: modulo by zero");
            return a % b;
        }
        /**
         * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
         * overflow (when the result is negative).
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {trySub}.
         *
         * Counterpart to Solidity's `-` operator.
         *
         * Requirements:
         *
         * - Subtraction cannot overflow.
         */
        function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
            require(b <= a, errorMessage);
            return a - b;
        }
        /**
         * @dev Returns the integer division of two unsigned integers, reverting with custom message on
         * division by zero. The result is rounded towards zero.
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {tryDiv}.
         *
         * Counterpart to Solidity's `/` operator. Note: this function uses a
         * `revert` opcode (which leaves remaining gas untouched) while Solidity
         * uses an invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
            require(b > 0, errorMessage);
            return a / b;
        }
        /**
         * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
         * reverting with custom message when dividing by zero.
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {tryMod}.
         *
         * Counterpart to Solidity's `%` operator. This function uses a `revert`
         * opcode (which leaves remaining gas untouched) while Solidity uses an
         * invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.6.0 <0.8.0;
    /*
     * @dev Provides information about the current execution context, including the
     * sender of the transaction and its data. While these are generally available
     * via msg.sender and msg.data, they should not be accessed in such a direct
     * manner, since when dealing with GSN meta-transactions the account sending and
     * paying for execution may not be the actual sender (as far as an application
     * is concerned).
     *
     * This contract is only required for intermediate, library-like contracts.
     */
    abstract contract Context {
        function _msgSender() internal view virtual returns (address payable) {
            return msg.sender;
        }
        function _msgData() internal view virtual returns (bytes memory) {
            this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
            return msg.data;
        }
    }
    

    File 8 of 8: UniswapV2Pair
    // SPDX-License-Identifier: MIT
    pragma solidity =0.6.12;
    import './UniswapV2ERC20.sol';
    import './libraries/Math.sol';
    import './libraries/UQ112x112.sol';
    import './interfaces/IERC20.sol';
    import './interfaces/IUniswapV2Factory.sol';
    import './interfaces/IUniswapV2Callee.sol';
    interface IMigrator {
        // Return the desired amount of liquidity token that the migrator wants.
        function desiredLiquidity() external view returns (uint256);
    }
    contract UniswapV2Pair is UniswapV2ERC20 {
        using SafeMathUniswap  for uint;
        using UQ112x112 for uint224;
        uint public constant MINIMUM_LIQUIDITY = 10**3;
        bytes4 private constant SELECTOR = bytes4(keccak256(bytes('transfer(address,uint256)')));
        address public factory;
        address public token0;
        address public token1;
        uint112 private reserve0;           // uses single storage slot, accessible via getReserves
        uint112 private reserve1;           // uses single storage slot, accessible via getReserves
        uint32  private blockTimestampLast; // uses single storage slot, accessible via getReserves
        uint public price0CumulativeLast;
        uint public price1CumulativeLast;
        uint public kLast; // reserve0 * reserve1, as of immediately after the most recent liquidity event
        uint public totalFee; // total fee (parts per thousand) charged for a swap
        uint public alpha; // numerator for the protocol fee factor
        uint public beta; // denominator for the protocol fee factor
        uint private unlocked = 1;
        modifier lock() {
            require(unlocked == 1, 'UniswapV2: LOCKED');
            unlocked = 0;
            _;
            unlocked = 1;
        }
        function getReserves() public view returns (uint112 _reserve0, uint112 _reserve1, uint32 _blockTimestampLast) {
            _reserve0 = reserve0;
            _reserve1 = reserve1;
            _blockTimestampLast = blockTimestampLast;
        }
        function _safeTransfer(address token, address to, uint value) private {
            (bool success, bytes memory data) = token.call(abi.encodeWithSelector(SELECTOR, to, value));
            require(success && (data.length == 0 || abi.decode(data, (bool))), 'UniswapV2: TRANSFER_FAILED');
        }
        event Mint(address indexed sender, uint amount0, uint amount1);
        event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
        event Swap(
            address indexed sender,
            uint amount0In,
            uint amount1In,
            uint amount0Out,
            uint amount1Out,
            address indexed to
        );
        event Sync(uint112 reserve0, uint112 reserve1);
        event FeeUpdated(uint totalFee, uint alpha, uint beta);
        constructor() public {
            factory = msg.sender;
        }
        // called once by the factory at time of deployment
        function initialize(address _token0, address _token1, uint _totalFee, uint _alpha, uint _beta) external {
            require(msg.sender == factory, 'UniswapV2: FORBIDDEN'); // sufficient check
            require(_alpha > 0,"_alpha must be greater than 0");
            require(_beta > _alpha,"beta should always be later than alpha");
            require(_totalFee > 0,"totalFee should not be 0, which will allow free flash swap");
            token0 = _token0;
            token1 = _token1;
            totalFee = _totalFee;
            alpha = _alpha;
            beta = _beta;
        }
        function updateFee(uint _totalFee, uint _alpha, uint _beta) external {
            require(msg.sender == factory, 'UniswapV2: FORBIDDEN');
            totalFee = _totalFee;
            alpha = _alpha;
            beta = _beta;
            emit FeeUpdated(_totalFee, _alpha, _beta);
        }
        // update reserves and, on the first call per block, price accumulators
        function _update(uint balance0, uint balance1, uint112 _reserve0, uint112 _reserve1) private {
            require(balance0 <= uint112(-1) && balance1 <= uint112(-1), 'UniswapV2: OVERFLOW');
            uint32 blockTimestamp = uint32(block.timestamp % 2**32);
            uint32 timeElapsed = blockTimestamp - blockTimestampLast; // overflow is desired
            if (timeElapsed > 0 && _reserve0 != 0 && _reserve1 != 0) {
                // * never overflows, and + overflow is desired
                price0CumulativeLast += uint(UQ112x112.encode(_reserve1).uqdiv(_reserve0)) * timeElapsed;
                price1CumulativeLast += uint(UQ112x112.encode(_reserve0).uqdiv(_reserve1)) * timeElapsed;
            }
            reserve0 = uint112(balance0);
            reserve1 = uint112(balance1);
            blockTimestampLast = blockTimestamp;
            emit Sync(reserve0, reserve1);
        }
        // if fee is on, mint liquidity equivalent to alpha/beta of the growth in sqrt(k)
        function _mintFee(uint112 _reserve0, uint112 _reserve1) private returns (bool feeOn) {
            address feeTo = IUniswapV2Factory(factory).feeTo();
            feeOn = feeTo != address(0);
            uint _kLast = kLast; // gas savings
            if (feeOn) {
                if (_kLast != 0) {
                    uint rootK = Math.sqrt(uint(_reserve0).mul(_reserve1));
                    uint rootKLast = Math.sqrt(_kLast);
                    if (rootK > rootKLast) {
                        uint numerator = totalSupply.mul(rootK.sub(rootKLast)).mul(alpha);
                        uint denominator = rootK.mul(beta.sub(alpha)).add(rootKLast.mul(alpha));
                        uint liquidity = numerator / denominator;
                        if (liquidity > 0) _mint(feeTo, liquidity);
                    }
                }
            } else if (_kLast != 0) {
                kLast = 0;
            }
        }
        // this low-level function should be called from a contract which performs important safety checks
        function mint(address to) external lock returns (uint liquidity) {
            (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
            uint balance0 = IERC20Uniswap(token0).balanceOf(address(this));
            uint balance1 = IERC20Uniswap(token1).balanceOf(address(this));
            uint amount0 = balance0.sub(_reserve0);
            uint amount1 = balance1.sub(_reserve1);
            bool feeOn = _mintFee(_reserve0, _reserve1);
            uint _totalSupply = totalSupply; // gas savings, must be defined here since totalSupply can update in _mintFee
            if (_totalSupply == 0) {
                address migrator = IUniswapV2Factory(factory).migrator();
                if (msg.sender == migrator) {
                    liquidity = IMigrator(migrator).desiredLiquidity();
                    require(liquidity > 0 && liquidity != uint256(-1), "Bad desired liquidity");
                } else {
                    require(migrator == address(0), "Must not have migrator");
                    liquidity = Math.sqrt(amount0.mul(amount1)).sub(MINIMUM_LIQUIDITY);
                    _mint(address(0), MINIMUM_LIQUIDITY); // permanently lock the first MINIMUM_LIQUIDITY tokens
                }
            } else {
                liquidity = Math.min(amount0.mul(_totalSupply) / _reserve0, amount1.mul(_totalSupply) / _reserve1);
            }
            require(liquidity > 0, 'UniswapV2: INSUFFICIENT_LIQUIDITY_MINTED');
            _mint(to, liquidity);
            _update(balance0, balance1, _reserve0, _reserve1);
            if (feeOn) kLast = uint(reserve0).mul(reserve1); // reserve0 and reserve1 are up-to-date
            emit Mint(msg.sender, amount0, amount1);
        }
        // this low-level function should be called from a contract which performs important safety checks
        function burn(address to) external lock returns (uint amount0, uint amount1) {
            (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
            address _token0 = token0;                                // gas savings
            address _token1 = token1;                                // gas savings
            uint balance0 = IERC20Uniswap(_token0).balanceOf(address(this));
            uint balance1 = IERC20Uniswap(_token1).balanceOf(address(this));
            uint liquidity = balanceOf[address(this)];
            bool feeOn = _mintFee(_reserve0, _reserve1);
            uint _totalSupply = totalSupply; // gas savings, must be defined here since totalSupply can update in _mintFee
            amount0 = liquidity.mul(balance0) / _totalSupply; // using balances ensures pro-rata distribution
            amount1 = liquidity.mul(balance1) / _totalSupply; // using balances ensures pro-rata distribution
            require(amount0 > 0 && amount1 > 0, 'UniswapV2: INSUFFICIENT_LIQUIDITY_BURNED');
            _burn(address(this), liquidity);
            _safeTransfer(_token0, to, amount0);
            _safeTransfer(_token1, to, amount1);
            balance0 = IERC20Uniswap(_token0).balanceOf(address(this));
            balance1 = IERC20Uniswap(_token1).balanceOf(address(this));
            _update(balance0, balance1, _reserve0, _reserve1);
            if (feeOn) kLast = uint(reserve0).mul(reserve1); // reserve0 and reserve1 are up-to-date
            emit Burn(msg.sender, amount0, amount1, to);
        }
        // this low-level function should be called from a contract which performs important safety checks
        function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external lock {
            require(amount0Out > 0 || amount1Out > 0, 'UniswapV2: INSUFFICIENT_OUTPUT_AMOUNT');
            (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
            require(amount0Out < _reserve0 && amount1Out < _reserve1, 'UniswapV2: INSUFFICIENT_LIQUIDITY');
            uint balance0;
            uint balance1;
            { // scope for _token{0,1}, avoids stack too deep errors
            address _token0 = token0;
            address _token1 = token1;
            require(to != _token0 && to != _token1, 'UniswapV2: INVALID_TO');
            if (amount0Out > 0) _safeTransfer(_token0, to, amount0Out); // optimistically transfer tokens
            if (amount1Out > 0) _safeTransfer(_token1, to, amount1Out); // optimistically transfer tokens
            if (data.length > 0) IUniswapV2Callee(to).uniswapV2Call(msg.sender, amount0Out, amount1Out, data);
            balance0 = IERC20Uniswap(_token0).balanceOf(address(this));
            balance1 = IERC20Uniswap(_token1).balanceOf(address(this));
            }
            uint amount0In = balance0 > _reserve0 - amount0Out ? balance0 - (_reserve0 - amount0Out) : 0;
            uint amount1In = balance1 > _reserve1 - amount1Out ? balance1 - (_reserve1 - amount1Out) : 0;
            require(amount0In > 0 || amount1In > 0, 'UniswapV2: INSUFFICIENT_INPUT_AMOUNT');
            { // scope for reserve{0,1}Adjusted, avoids stack too deep errors
            uint balance0Adjusted = balance0.mul(1000).sub(amount0In.mul(totalFee));
            uint balance1Adjusted = balance1.mul(1000).sub(amount1In.mul(totalFee));
            require(balance0Adjusted.mul(balance1Adjusted) >= uint(_reserve0).mul(_reserve1).mul(1000**2), 'UniswapV2: K');
            }
            _update(balance0, balance1, _reserve0, _reserve1);
            emit Swap(msg.sender, amount0In, amount1In, amount0Out, amount1Out, to);
        }
        // force balances to match reserves
        function skim(address to) external lock {
            address _token0 = token0; // gas savings
            address _token1 = token1; // gas savings
            _safeTransfer(_token0, to, IERC20Uniswap(_token0).balanceOf(address(this)).sub(reserve0));
            _safeTransfer(_token1, to, IERC20Uniswap(_token1).balanceOf(address(this)).sub(reserve1));
        }
        // force reserves to match balances
        function sync() external lock {
            _update(IERC20Uniswap(token0).balanceOf(address(this)), IERC20Uniswap(token1).balanceOf(address(this)), reserve0, reserve1);
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity =0.6.12;
    import './libraries/SafeMath.sol';
    contract UniswapV2ERC20 {
        using SafeMathUniswap for uint;
        string public constant name = 'ShibaSwap LP Token';
        string public constant symbol = 'SSLP';
        uint8 public constant decimals = 18;
        uint  public totalSupply;
        mapping(address => uint) public balanceOf;
        mapping(address => mapping(address => uint)) public allowance;
        bytes32 public DOMAIN_SEPARATOR;
        // keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
        bytes32 public constant PERMIT_TYPEHASH = 0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9;
        mapping(address => uint) public nonces;
        event Approval(address indexed owner, address indexed spender, uint value);
        event Transfer(address indexed from, address indexed to, uint value);
        constructor() public {
            uint chainId;
            assembly {
                chainId := chainid()
            }
            DOMAIN_SEPARATOR = keccak256(
                abi.encode(
                    keccak256('EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)'),
                    keccak256(bytes(name)),
                    keccak256(bytes('1')),
                    chainId,
                    address(this)
                )
            );
        }
        function _mint(address to, uint value) internal {
            totalSupply = totalSupply.add(value);
            balanceOf[to] = balanceOf[to].add(value);
            emit Transfer(address(0), to, value);
        }
        function _burn(address from, uint value) internal {
            balanceOf[from] = balanceOf[from].sub(value);
            totalSupply = totalSupply.sub(value);
            emit Transfer(from, address(0), value);
        }
        function _approve(address owner, address spender, uint value) private {
            allowance[owner][spender] = value;
            emit Approval(owner, spender, value);
        }
        function _transfer(address from, address to, uint value) private {
            balanceOf[from] = balanceOf[from].sub(value);
            balanceOf[to] = balanceOf[to].add(value);
            emit Transfer(from, to, value);
        }
        function approve(address spender, uint value) external returns (bool) {
            _approve(msg.sender, spender, value);
            return true;
        }
        function transfer(address to, uint value) external returns (bool) {
            _transfer(msg.sender, to, value);
            return true;
        }
        function transferFrom(address from, address to, uint value) external returns (bool) {
            if (allowance[from][msg.sender] != uint(-1)) {
                allowance[from][msg.sender] = allowance[from][msg.sender].sub(value);
            }
            _transfer(from, to, value);
            return true;
        }
        function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external {
            require(deadline >= block.timestamp, 'UniswapV2: EXPIRED');
            bytes32 digest = keccak256(
                abi.encodePacked(
                    '\\x19\\x01',
                    DOMAIN_SEPARATOR,
                    keccak256(abi.encode(PERMIT_TYPEHASH, owner, spender, value, nonces[owner]++, deadline))
                )
            );
            address recoveredAddress = ecrecover(digest, v, r, s);
            require(recoveredAddress != address(0) && recoveredAddress == owner, 'UniswapV2: INVALID_SIGNATURE');
            _approve(owner, spender, value);
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity =0.6.12;
    // a library for performing various math operations
    library Math {
        function min(uint x, uint y) internal pure returns (uint z) {
            z = x < y ? x : y;
        }
        // babylonian method (https://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Babylonian_method)
        function sqrt(uint y) internal pure returns (uint z) {
            if (y > 3) {
                z = y;
                uint x = y / 2 + 1;
                while (x < z) {
                    z = x;
                    x = (y / x + x) / 2;
                }
            } else if (y != 0) {
                z = 1;
            }
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity =0.6.12;
    // a library for handling binary fixed point numbers (https://en.wikipedia.org/wiki/Q_(number_format))
    // range: [0, 2**112 - 1]
    // resolution: 1 / 2**112
    library UQ112x112 {
        uint224 constant Q112 = 2**112;
        // encode a uint112 as a UQ112x112
        function encode(uint112 y) internal pure returns (uint224 z) {
            z = uint224(y) * Q112; // never overflows
        }
        // divide a UQ112x112 by a uint112, returning a UQ112x112
        function uqdiv(uint224 x, uint112 y) internal pure returns (uint224 z) {
            z = x / uint224(y);
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.5.0;
    interface IERC20Uniswap {
        event Approval(address indexed owner, address indexed spender, uint value);
        event Transfer(address indexed from, address indexed to, uint value);
        function name() external view returns (string memory);
        function symbol() external view returns (string memory);
        function decimals() external view returns (uint8);
        function totalSupply() external view returns (uint);
        function balanceOf(address owner) external view returns (uint);
        function allowance(address owner, address spender) external view returns (uint);
        function approve(address spender, uint value) external returns (bool);
        function transfer(address to, uint value) external returns (bool);
        function transferFrom(address from, address to, uint value) external returns (bool);
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.5.0;
    interface IUniswapV2Factory {
        event PairCreated(address indexed token0, address indexed token1, address pair, uint);
        function feeTo() external view returns (address);
        function feeToSetter() external view returns (address);
        function migrator() external view returns (address);
        function totalFeeTopCoin() external view returns (uint);
        function alphaTopCoin() external view returns (uint);
        function betaTopCoin() external view returns (uint);
        function totalFeeRegular() external view returns (uint);
        function alphaRegular() external view returns (uint);
        function betaRegular() external view returns (uint);
        function topCoins(address token) external view returns (bool isTopCoin);
        function getPair(address tokenA, address tokenB) external view returns (address pair);
        function allPairs(uint) external view returns (address pair);
        function allPairsLength() external view returns (uint);
        function createPair(address tokenA, address tokenB) external returns (address pair);
        function setFeeTo(address) external;
        function setFeeToSetter(address) external;
        function setMigrator(address) external;
    }
    // SPDX-License-Identifier: MIT
    pragma solidity >=0.5.0;
    interface IUniswapV2Callee {
        function uniswapV2Call(address sender, uint amount0, uint amount1, bytes calldata data) external;
    }
    // SPDX-License-Identifier: MIT
    pragma solidity =0.6.12;
    // a library for performing overflow-safe math, courtesy of DappHub (https://github.com/dapphub/ds-math)
    library SafeMathUniswap {
        function add(uint x, uint y) internal pure returns (uint z) {
            require((z = x + y) >= x, 'ds-math-add-overflow');
        }
        function sub(uint x, uint y) internal pure returns (uint z) {
            require((z = x - y) <= x, 'ds-math-sub-underflow');
        }
        function mul(uint x, uint y) internal pure returns (uint z) {
            require(y == 0 || (z = x * y) / y == x, 'ds-math-mul-overflow');
        }
    }