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Created using remix-ide: Realtime Ethereum Contract Compiler and Runtime. Load this file by pasting this gists URL or ID at https://remix.ethereum.org/#version=soljson-v0.5.7+commit.6da8b019.js&optimize=false&gist=
pragma solidity ^0.5.7;
library SafeMath {
function mul(uint256 a, uint256 b) internal pure returns (uint256) {
if (a == 0) {
return 0;
}
uint256 c = a * b;
require(c / a == b);
return c;
}
function div(uint256 a, uint256 b) internal pure returns (uint256) {
require(b > 0);
uint256 c = a / b;
return c;
}
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
require(b <= a);
uint256 c = a - b;
return c;
}
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a);
return c;
}
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
require(b != 0);
return a % b;
}
}
contract ERC20Standard {
using SafeMath for uint256;
uint public totalSupply;
string public name;
uint8 public decimals;
string public symbol;
string public version;
mapping (address => uint256) balances;
mapping (address => mapping (address => uint)) allowed;
//Fix for short address attack against ERC20
modifier onlyPayloadSize(uint size) {
assert(msg.data.length == size + 4);
_;
}
function balanceOf(address _owner) public view returns (uint balance) {
return balances[_owner];
}
function transfer(address _recipient, uint _value) public onlyPayloadSize(2*32) {
require(balances[msg.sender] >= _value && _value > 0);
balances[msg.sender].sub(_value);
balances[_recipient].add(_value);
emit Transfer(msg.sender, _recipient, _value);
}
function transferFrom(address _from, address _to, uint _value) public {
require(balances[_from] >= _value && allowed[_from][msg.sender] >= _value && _value > 0);
balances[_to].add(_value);
balances[_from].sub(_value);
allowed[_from][msg.sender].sub(_value);
emit Transfer(_from, _to, _value);
}
function approve(address _spender, uint _value) public {
allowed[msg.sender][_spender] = _value;
emit Approval(msg.sender, _spender, _value);
}
function allowance(address _spender, address _owner) public view returns (uint balance) {
return allowed[_owner][_spender];
}
//Event which is triggered to log all transfers to this contract's event log
event Transfer(
address indexed _from,
address indexed _to,
uint _value
);
//Event which is triggered whenever an owner approves a new allowance for a spender.
event Approval(
address indexed _owner,
address indexed _spender,
uint _value
);
}
pragma solidity ^0.5.2;
import "./ERC20Standard.sol";
contract TestToken is ERC20Standard {
constructor() public {
totalSupply = 100000000;
name = "Test Token";
decimals = 6;
symbol = "TST";
version = "1.0";
balances[msg.sender] = totalSupply;
}
}
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