Contract Source Code:
File 1 of 1 : LUCKYToken
pragma solidity 0.5.15;
/**
* @title SafeMath
* @dev Unsigned math operations with safety checks that revert on error.
*/
library SafeMath {
/**
* @dev Multiplie two unsigned integers, revert on overflow.
*/
function mul(uint256 a, uint256 b) internal pure returns (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-solidity/pull/522
if (a == 0) {
return 0;
}
uint256 c = a * b;
require(c / a == b);
return c;
}
/**
* @dev Integer division of two unsigned integers truncating the quotient, revert on division by zero.
*/
function div(uint256 a, uint256 b) internal pure returns (uint256) {
// Solidity only automatically asserts when dividing by 0
require(b > 0);
uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
/**
* @dev Subtract two unsigned integers, revert on underflow (i.e. if subtrahend is greater than minuend).
*/
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
require(b <= a);
uint256 c = a - b;
return c;
}
/**
* @dev Add two unsigned integers, revert on overflow.
*/
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a);
return c;
}
}
/**
* @title ERC20 interface
* @dev See https://eips.ethereum.org/EIPS/eip-20
*/
interface IERC20 {
function transfer(address to, uint256 value) external returns (bool);
function approve(address spender, uint256 value) external returns (bool);
function transferFrom(address from, address to, uint256 value) external returns (bool);
function totalSupply() external view returns (uint256);
function balanceOf(address who) external view returns (uint256);
function allowance(address owner, address spender) external view returns (uint256);
event Transfer(address indexed from, address indexed to, uint256 value);
event Approval(address indexed owner, address indexed spender, uint256 value);
}
/**
* @title Standard ERC20 token
* @dev Implementation of the basic standard token.
*/
contract StandardToken is IERC20 {
using SafeMath for uint256;
mapping (address => uint256) internal _balances;
mapping (address => mapping (address => uint256)) internal _allowed;
uint256 internal _totalSupply;
/**
* @dev Total number of tokens in existence.
*/
function totalSupply() public view returns (uint256) {
return _totalSupply;
}
/**
* @dev Get the balance of the specified address.
* @param owner The address to query the balance of.
* @return A uint256 representing the amount owned by the passed address.
*/
function balanceOf(address owner) public view returns (uint256) {
return _balances[owner];
}
/**
* @dev Function to check the amount of tokens that an owner allowed to a spender.
* @param owner The address which owns the funds.
* @param spender The address which will spend the funds.
* @return A uint256 specifying the amount of tokens still available for the spender.
*/
function allowance(address owner, address spender) public view returns (uint256) {
return _allowed[owner][spender];
}
/**
* @dev Transfer tokens to a specified address.
* @param to The address to transfer to.
* @param value The amount to be transferred.
*/
function transfer(address to, uint256 value) public returns (bool) {
_transfer(msg.sender, to, value);
return true;
}
/**
* @dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
* 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
* @param spender The address which will spend the funds.
* @param value The amount of tokens to be spent.
*/
function approve(address spender, uint256 value) public returns (bool) {
_approve(msg.sender, spender, value);
return true;
}
/**
* @dev Transfer tokens from one address to another.
* Note that while this function emits an Approval event, this is not required as per the specification,
* and other compliant implementations may not emit the event.
* @param from The address which you want to send tokens from.
* @param to The address which you want to transfer to.
* @param value The amount of tokens to be transferred.
*/
function transferFrom(address from, address to, uint256 value) public returns (bool) {
_transfer(from, to, value);
_approve(from, msg.sender, _allowed[from][msg.sender].sub(value));
return true;
}
/**
* @dev Increase the amount of tokens that an owner allowed to a spender.
* approve should be called when _allowed[msg.sender][spender] == 0. To increment
* allowed value is better to use this function to avoid 2 calls (and wait until
* the first transaction is mined)
* From MonolithDAO Token.sol
* Emits an Approval event.
* @param spender The address which will spend the funds.
* @param addedValue The amount of tokens to increase the allowance by.
*/
function increaseAllowance(address spender, uint256 addedValue) public returns (bool) {
_approve(msg.sender, spender, _allowed[msg.sender][spender].add(addedValue));
return true;
}
/**
* @dev Decrease the amount of tokens that an owner allowed to a spender.
* approve should be called when _allowed[msg.sender][spender] == 0. To decrement
* allowed value is better to use this function to avoid 2 calls (and wait until
* the first transaction is mined)
* From MonolithDAO Token.sol
* Emits an Approval event.
* @param spender The address which will spend the funds.
* @param subtractedValue The amount of tokens to decrease the allowance by.
*/
function decreaseAllowance(address spender, uint256 subtractedValue) public returns (bool) {
_approve(msg.sender, spender, _allowed[msg.sender][spender].sub(subtractedValue));
return true;
}
/**
* @dev Transfer tokens for a specified address.
* @param from The address to transfer from.
* @param to The address to transfer to.
* @param value The amount to be transferred.
*/
function _transfer(address from, address to, uint256 value) internal {
require(to != address(0), "Cannot transfer to the zero address");
_balances[from] = _balances[from].sub(value);
_balances[to] = _balances[to].add(value);
emit Transfer(from, to, value);
}
/**
* @dev Approve an address to spend another addresses' tokens.
* @param owner The address that owns the tokens.
* @param spender The address that will spend the tokens.
* @param value The number of tokens that can be spent.
*/
function _approve(address owner, address spender, uint256 value) internal {
require(spender != address(0), "Cannot approve to the zero address");
require(owner != address(0), "Setter cannot be the zero address");
_allowed[owner][spender] = value;
emit Approval(owner, spender, value);
}
/**
* @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 value) internal {
require(account != address(0), "StandardToken: burn from the zero address");
_balances[account] = _balances[account].sub(value);
_totalSupply = _totalSupply.sub(value);
emit Transfer(account, address(0), value);
}
/**
* @dev Destroys `amount` tokens from `account`.`amount` is then deducted
* from the caller's allowance.
*
* See {_burn} and {_approve}.
*/
function _burnFrom(address account, uint256 amount) internal {
_burn(account, amount);
_approve(account, msg.sender, _allowed[account][msg.sender].sub(amount));
}
}
/**
* @title Ownable
* @dev The Ownable contract has an owner address, and provides basic authorization control
* functions, this simplifies the implementation of "user permissions".
*/
contract Ownable {
address internal _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @return the address of the owner.
*/
function owner() public view returns (address) {
return _owner;
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
require(isOwner(), "Ownable: the caller must be owner");
_;
}
/**
* @return true if `msg.sender` is the owner of the contract.
*/
function isOwner() public view returns (bool) {
return msg.sender == _owner;
}
/**
* @dev Allows the current owner to transfer control of the contract to a newOwner.
* @param newOwner The address to transfer ownership to.
*/
function transferOwnership(address newOwner) public onlyOwner {
_transferOwnership(newOwner);
}
/**
* @dev Transfers control of the contract to a newOwner.
* @param newOwner The address to transfer ownership to.
*/
function _transferOwnership(address newOwner) internal {
require(newOwner != address(0), "Ownable: cannot transfer control of the contract to zero address");
emit OwnershipTransferred(_owner, newOwner);
_owner = newOwner;
}
}
/**
* @title Pausable
* @dev Base contract which allows children to implement an emergency stop mechanism.
*/
contract Pausable is Ownable {
event Pause();
event Unpause();
bool public paused = false;
/**
* @dev Modifier to make a function callable only when the contract is not paused.
*/
modifier whenNotPaused() {
require(!paused, "Pausable: only when the contract is not paused");
_;
}
/**
* @dev Modifier to make a function callable only when the contract is paused.
*/
modifier whenPaused() {
require(paused, "Pausable: only when the contract is paused");
_;
}
/**
* @dev Called by the owner to pause, trigger stopped state
*/
function pause() public onlyOwner whenNotPaused {
paused = true;
emit Pause();
}
/**
* @dev Called by the owner to unpause, return to normal state
*/
function unpause() public onlyOwner whenPaused {
paused = false;
emit Unpause();
}
}
/**
* @title PausableToken
* @dev ERC20 modified with pausable transfers.
*/
contract PausableToken is StandardToken, Pausable {
function transfer(address _to, uint256 _value) public whenNotPaused returns (bool) {
return super.transfer(_to, _value);
}
function transferFrom(address _from, address _to, uint256 _value) public whenNotPaused returns (bool) {
return super.transferFrom(_from, _to, _value);
}
function approve(address _spender, uint256 _value) public whenNotPaused returns (bool) {
return super.approve(_spender, _value);
}
function increaseAllowance(address _spender, uint _addedValue) public whenNotPaused returns (bool success) {
return super.increaseAllowance(_spender, _addedValue);
}
function decreaseAllowance(address _spender, uint _subtractedValue) public whenNotPaused returns (bool success) {
return super.decreaseAllowance(_spender, _subtractedValue);
}
}
/**
* @title BurnableToken
* @dev Implement the function of ERC20 token burning.
*/
contract BurnableToken is StandardToken, Ownable {
/**
* @dev Destroys `amount` tokens from the caller.
*
* See {ERC20-_burn}.
*/
function burn(uint256 amount) public onlyOwner {
_burn(msg.sender, amount);
}
/**
* @dev See {ERC20-_burnFrom}.
*/
function burnFrom(address account, uint256 amount) public onlyOwner {
_burnFrom(account, amount);
}
}
contract LUCKYToken is BurnableToken, PausableToken {
string public constant name = "LUCKY";
string public constant symbol = "LUCKY";
uint8 public constant decimals = 18;
uint256 internal constant INIT_TOTALSUPPLY = 10000000000;
address internal constant _tokenOwner = 0x6d881594c2638e21eF8BE440d341AECE3C81875F;
/**
* @dev Constructor, initialize the basic information of contract.
*/
constructor() public {
_totalSupply = INIT_TOTALSUPPLY * 10 ** uint256(decimals);
_owner = _tokenOwner;
emit OwnershipTransferred(address(0), _owner);
_balances[_owner] = _totalSupply;
emit Transfer(address(0), _owner, _totalSupply);
}
}