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Token.sol
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Token.sol
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// SPDX-License-Identifier: MIT
pragma solidity ^0.8.6;
contract Token {
string public name;
string public symbol;
uint256 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(string memory _name, string memory _symbol, uint _decimals, uint _totalSupply) {
name = _name;
symbol = _symbol;
decimals = _decimals;
totalSupply = _totalSupply;
balanceOf[msg.sender] = totalSupply;
}
function transfer(address _to, uint256 _value) external returns (bool success) {
require(balanceOf[msg.sender] >= _value);
_transfer(msg.sender, _to, _value);
return true;
}
function _transfer(address _from, address _to, uint256 _value) internal {
require(_to != address(0));
balanceOf[_from] = balanceOf[_from] - (_value);
balanceOf[_to] = balanceOf[_to] + (_value);
emit Transfer(_from, _to, _value);
}
function approve(address _spender, uint256 _value) external returns (bool) {
require(_spender != address(0));
allowance[msg.sender][_spender] = _value;
emit Approval(msg.sender, _spender, _value);
return true;
}
function transferFrom(address _from, address _to, uint256 _value) external returns (bool) {
require(_value <= balanceOf[_from]);
require(_value <= allowance[_from][msg.sender]);
allowance[_from][msg.sender] = allowance[_from][msg.sender] - (_value);
_transfer(_from, _to, _value);
return true;
}
}