/*
    Its part of ethereum public blockchain.
    Developed by AsaCoin Development Team 2018.
*/

pragma solidity ^0.4.21;

contract ERC20Interface {
    uint256 public totalSupply;

    function balanceOf(address _owner) public view returns (uint256 balance);

    function transfer(address _to, uint256 _value) public returns (bool success);

    function transferFrom(address _from, address _to, uint256 _value) public returns (bool success);

    function approve(address _spender, uint256 _value) public returns (bool success);

    function allowance(address _owner, address _spender) public view returns (uint256 remaining);

    event Transfer(address indexed _from, address indexed _to, uint256 _value);
    event Approval(address indexed _owner, address indexed _spender, uint256 _value);
}



contract Ownable {
  address public owner;


  event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);


  constructor() public {
    owner = msg.sender;
  }



  modifier onlyOwner() {
    require(msg.sender == owner);
    _;
  }


 
  function transferOwnership(address newOwner) public onlyOwner {
    require(newOwner != address(0));
    emit OwnershipTransferred(owner, newOwner);
    owner = newOwner;
  }

}

contract AsaCoin is ERC20Interface, Ownable {

    uint256 constant private MAX_UINT256 = 2**256 - 1;
    mapping (address => uint256) public balances;
    mapping (address => mapping (address => uint256)) public allowed;
   
    string public name;                   
    uint8 public decimals;                
    string public symbol;                 
    uint256 public totalSupply;
    uint256 public tokenDecimal = 1000000000000000000;
  

    constructor() public {
        totalSupply = 450000000 * tokenDecimal;
        balances[msg.sender] = totalSupply;           
        name = "AsaCoin";                                   
        decimals = 18;                            
        symbol = "ASA";                               
    }

    function transfer(address _to, uint256 _value) public returns (bool success) {
        require(balances[msg.sender] >= _value);
        balances[msg.sender] -= _value;
        balances[_to] += _value;
        emit Transfer(msg.sender, _to, _value); 
        return true;
    }

    function transferFrom(address _from, address _to, uint256 _value) onlyOwner public returns (bool success) {
        require(balances[_from] >= _value);
        balances[_to] += _value;
        balances[_from] -= _value;
		allowed[_from][msg.sender] -= _value;
        
        emit Transfer(_from, _to, _value); 
        return true;
    }

    function balanceOf(address _owner) public view returns (uint256 balance) {
        return balances[_owner];
    }

    function approve(address _spender, uint256 _value) public returns (bool success) {
        allowed[msg.sender][_spender] = _value;
        emit Approval(msg.sender, _spender, _value); 
        return true;
    }

    function allowance(address _owner, address _spender) public view returns (uint256 remaining) {
        return allowed[_owner][_spender];
    }
    
    function () payable public {
		balances[msg.sender] += msg.value;
	}
}