Contract Source Code:
File 1 of 1 : ERC20TOKEN
pragma solidity ^0.5.7;
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);
}
contract Ownable {
address private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
constructor () internal {
_owner = msg.sender;
emit OwnershipTransferred(address(0), _owner);
}
function owner() public view returns (address) {
return _owner;
}
modifier onlyOwner() {
require(isOwner());
_;
}
function isOwner() public view returns (bool) {
return msg.sender == _owner;
}
function renounceOwnership() public onlyOwner {
emit OwnershipTransferred(_owner, address(0));
_owner = address(0);
}
function transferOwnership(address newOwner) public onlyOwner {
_transferOwnership(newOwner);
}
function _transferOwnership(address newOwner) internal {
require(newOwner != address(0));
emit OwnershipTransferred(_owner, newOwner);
_owner = newOwner;
}
}
contract SafeMath {
function safeMul(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a * b;
assert(a == 0 || c / a == b);
return c;
}
function safeDiv(uint256 a, uint256 b) internal pure returns (uint256) {
assert(b > 0);
uint256 c = a / b;
assert(a == b * c + a % b);
return c;
}
function safeSub(uint256 a, uint256 b) internal pure returns (uint256) {
assert(b <= a);
return a - b;
}
function safeAdd(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
assert(c>=a && c>=b);
return c;
}
}
contract ERC20TOKEN is Ownable, SafeMath, IERC20{
string public name;
string public symbol;
uint8 public decimals;
uint256 public totalSupply;
mapping (address => uint256) public balanceOf;
mapping (address => mapping (address => uint256)) public allowance;
event Transfer(address indexed from, address indexed to, uint256 value);
event Approval(address indexed owner, address indexed spender, uint256 value);
constructor() public {
balanceOf[msg.sender] = 1000000000000000000000000000;
totalSupply = 1000000000000000000000000000;
name = "DU";
symbol = "DU";
decimals = 18;
}
function transfer(address _to, uint256 _value) public returns (bool) {
require(_to != address(0));
require(_value > 0);
require(balanceOf[msg.sender] >= _value);
require(balanceOf[_to] + _value >= balanceOf[_to]);
uint previousBalances = balanceOf[msg.sender] + balanceOf[_to];
balanceOf[msg.sender] = SafeMath.safeSub(balanceOf[msg.sender], _value);
balanceOf[_to] = SafeMath.safeAdd(balanceOf[_to], _value);
emit Transfer(msg.sender, _to, _value);
assert(balanceOf[msg.sender]+balanceOf[_to]==previousBalances);
return true;
}
function approve(address _spender, uint256 _value) public returns (bool success) {
require((_value == 0) || (allowance[msg.sender][_spender] == 0));
allowance[msg.sender][_spender] = _value;
emit Approval(msg.sender, _spender, _value);
return true;
}
function transferFrom(address _from, address _to, uint256 _value) public returns (bool success) {
require (_to != address(0));
require (_value > 0);
require (balanceOf[_from] >= _value) ;
require (balanceOf[_to] + _value > balanceOf[_to]);
require (_value <= allowance[_from][msg.sender]);
balanceOf[_from] = SafeMath.safeSub(balanceOf[_from], _value);
balanceOf[_to] = SafeMath.safeAdd(balanceOf[_to], _value);
allowance[_from][msg.sender] = SafeMath.safeSub(allowance[_from][msg.sender], _value);
emit Transfer(_from, _to, _value);
return true;
}
}