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@doey-default
Last active November 8, 2019 07:48
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pragma solidity ^0.5.0;
import "./SafeMath.sol";
interface IERC20 {
function totalSupply() external view returns (uint256);
function balanceOf(address account) external view returns (uint256);
function transfer(address recipient, uint256 amount) external returns (bool);
function allowance(address owner, address spender) external view returns (uint256);
function approve(address spender, uint256 amount) external returns (bool);
function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
event Transfer(address indexed from, address indexed to, uint256 value);
event Approval(address indexed owner, address indexed spender, uint256 value);
}
contract MyToken is IERC20 {
using SafeMath for uint;
string public constant name = "MyToken";
string public constant symbol = "MTK";
uint8 public constant decimals = 6;
uint private _totalSupply;
uint private totalProvided;
address payable private owner;
mapping(address => uint) private balances;
mapping(address => mapping(address => uint)) private allowed;
constructor() public
{
_totalSupply = 100000 * 10 ** uint(decimals);
owner = msg.sender;
balances[owner] = _totalSupply;
totalProvided = 0;
}
function totalSupply() external view returns (uint)
{
return _totalSupply;
}
function balanceOf(address _account) external view returns (uint)
{
return balances[_account];
}
function transfer(address _recipient, uint _amount) external returns (bool)
{
if (_amount > 0 && balances[msg.sender] >= _amount) {
balances[msg.sender] = balances[msg.sender].sub(_amount);
balances[_recipient] = balances[_recipient].add(_amount);
emit Transfer(msg.sender, _recipient, _amount);
return true;
}
return false;
}
function allowance(address _owner, address _spender) external view returns (uint)
{
return allowed[_owner][_spender];
}
function approve(address _spender, uint _amount) external returns (bool)
{
if (_amount > 0 && balances[msg.sender] >= _amount) {
allowed[msg.sender][_spender] = allowed[msg.sender][_spender].add(_amount);
emit Approval(msg.sender, _spender, _amount);
return true;
}
return false;
}
function transferFrom(address _sender, address _recipient, uint _amount) external returns (bool)
{
if (_amount > 0 && balances[_sender] >= _amount && allowed[_sender][msg.sender] >= _amount) {
allowed[_sender][msg.sender] = allowed[_sender][msg.sender].sub(_amount);
balances[_sender] = balances[_sender].sub(_amount);
balances[_recipient] = balances[_recipient].add(_amount);
emit Transfer(msg.sender, _recipient, _amount);
return true;
}
return false;
}
function burn(uint _amount) external onlyOwner returns (bool) {
if( _amount > 0 && balances[owner] >= _amount ) {
balances[owner] = balances[owner].sub(_amount);
_totalSupply = _totalSupply.sub(_amount);
return true;
}
return false;
}
function buyToken() payable external returns (bool) {
if(msg.value >= 0 && now < 1573111078
&& totalProvided.add(msg.value * 10000) <= _totalSupply
&& msg.value * 10000 <= balances[owner]){
uint _amount = msg.value * 10000;
balances[owner] = balances[owner].sub(_amount);
balances[msg.sender] = balances[msg.sender].add(_amount);
if(owner.send(msg.value)){
emit Transfer(owner, msg.sender, _amount);
totalProvided = totalProvided.add(msg.value * 10000);
return true;
} else {
revert();
}
}
return false;
}
modifier onlyOwner {
require(owner == msg.sender);
_;
}
}
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