文件 1 的 3:BrittoCoin.sol
pragma solidity ^0.7.4;
import "IERC20.sol";
import "SafeMath.sol";
contract BrittoCoin is IERC20 {
string public constant name = "Britto Coin";
string public constant symbol = "BRT";
uint8 public constant decimals = 18;
mapping(address => uint256) balances;
mapping(address => mapping (address => uint256)) allowed;
uint256 totalSupply_;
using SafeMath for uint256;
constructor() {
totalSupply_ = 441000000 * 1e18;
balances[msg.sender] = totalSupply_;
}
function totalSupply() public override view returns (uint256) {
return totalSupply_;
}
function balanceOf(address tokenOwner) public override view returns (uint256) {
return balances[tokenOwner];
}
function transfer(address receiver, uint256 numTokens) public override returns (bool) {
require(numTokens <= balances[msg.sender]);
balances[msg.sender] = balances[msg.sender].sub(numTokens);
balances[receiver] = balances[receiver].add(numTokens);
emit Transfer(msg.sender, receiver, numTokens);
return true;
}
function approve(address delegate, uint256 numTokens) public override returns (bool) {
allowed[msg.sender][delegate] = numTokens;
emit Approval(msg.sender, delegate, numTokens);
return true;
}
function allowance(address owner, address delegate) public override view returns (uint) {
return allowed[owner][delegate];
}
function transferFrom(address owner, address buyer, uint256 numTokens) public override returns (bool) {
require(numTokens <= balances[owner]);
require(numTokens <= allowed[owner][msg.sender]);
balances[owner] = balances[owner].sub(numTokens);
allowed[owner][msg.sender] = allowed[owner][msg.sender].sub(numTokens);
balances[buyer] = balances[buyer].add(numTokens);
emit Transfer(owner, buyer, numTokens);
return true;
}
}
文件 2 的 3:IERC20.sol
pragma solidity ^0.7.4;
interface IERC20 {
function totalSupply() external view returns (uint256);
function balanceOf(address account) external view returns (uint256);
function allowance(address owner, address spender) external view returns (uint256);
function transfer(address recipient, uint256 amount) external returns (bool);
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);
}
文件 3 的 3:SafeMath.sol
pragma solidity >=0.5.16;
library SafeMath {
function add(uint256 a, uint256 b) internal pure returns (uint256) {
uint256 c = a + b;
require(c >= a, "SafeMath: addition overflow");
return c;
}
function sub(uint256 a, uint256 b) internal pure returns (uint256) {
return sub(a, b, "SafeMath: subtraction overflow");
}
function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
require(b <= a, errorMessage);
uint256 c = a - b;
return c;
}
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;
}
function div(uint256 a, uint256 b) internal pure returns (uint256) {
return div(a, b, "SafeMath: division by zero");
}
function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
require(b > 0, errorMessage);
uint256 c = a / b;
return c;
}
function mod(uint256 a, uint256 b) internal pure returns (uint256) {
return mod(a, b, "SafeMath: modulo by zero");
}
function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
require(b != 0, errorMessage);
return a % b;
}
}
{
"compilationTarget": {
"BrittoCoin.sol": "BrittoCoin"
},
"evmVersion": "istanbul",
"libraries": {},
"metadata": {
"bytecodeHash": "ipfs"
},
"optimizer": {
"enabled": false,
"runs": 200
},
"remappings": []
}
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