pragma solidity ^0.5.11;

contract ERC20 {
  function balanceOf(address who) public view returns (uint256);
  function allowance(address owner, address spender) public view returns (uint256);
  function transferFrom(address from, address to, uint256 value) public returns (bool);
  function approve(address spender, uint256 value) public returns (bool);
  function transfer(address to, uint value) public returns(bool);
  event Transfer(address indexed from, address indexed to, uint value);
  event Approval(address indexed owner, address indexed spender, uint256 value);
  event Burn(address indexed from, uint256 value);
}

library SafeMath{
      function mul(uint256 a, uint256 b) internal pure returns (uint256) 
    {
        if (a == 0) {
        return 0;}
        uint256 c = a * b;
        assert(c / a == b);
        return c;
    }

    function div(uint256 a, uint256 b) internal pure returns (uint256) 
    {
        uint256 c = a / b;
        return c;
    }

    function sub(uint256 a, uint256 b) internal pure returns (uint256) 
    {
        assert(b <= a);
        return a - b;
    }

    function add(uint256 a, uint256 b) internal pure returns (uint256) 
    {
        uint256 c = a + b;
        assert(c >= a);
        return c;
    }

}
contract peen is ERC20 {
    
        using SafeMath for uint256;

    string internal _name;
    string internal _symbol;
    uint8 internal _decimals;
    uint256 internal _totalSupply;
    
    address internal  _admin;
    

    mapping (address => uint256) internal balances;
    mapping (address => mapping (address => uint256)) internal allowed;
  

    constructor() public {
        _admin = msg.sender;
        _symbol = "PEEN";  
        _name = "Peen"; 
        _decimals = 18; 
        _totalSupply = 200000* 10**uint(_decimals);
        balances[msg.sender]=_totalSupply;
       
    }
    
    modifier ownership()  {
    require(msg.sender == _admin);
        _;
    }
    
  
    function name() public view returns (string memory) 
    {
        return _name;
    }

    function symbol() public view returns (string memory) 
    {
        return _symbol;
    }

    function decimals() public view returns (uint8) 
    {
        return _decimals;
    }

    function totalSupply() public view returns (uint256) 
    {
        return _totalSupply;
    }

   function transfer(address _to, uint256 _value) public returns (bool) {
     require(_to != address(0));
     require(_value <= balances[msg.sender]);
     balances[msg.sender] = balances[msg.sender].sub(_value);
     balances[_to] = (balances[_to]).add( _value);
     emit ERC20.Transfer(msg.sender, _to, _value);
     return true;
   }

  function balanceOf(address _owner) public view returns (uint256 balance) {
    return balances[_owner];
   }

  function transferFrom(address _from, address _to, uint256 _value) public returns (bool) {
     require(_to != address(0));
     require(_value <= balances[_from]);
     require(_value <= allowed[_from][msg.sender]);

    balances[_from] = (balances[_from]).sub( _value);
    balances[_to] = (balances[_to]).add(_value);
    allowed[_from][msg.sender] = (allowed[_from][msg.sender]).sub(_value);
    emit ERC20.Transfer(_from, _to, _value);
     return true;
   }

   function approve(address _spender, uint256 _value) public returns (bool) {
     allowed[msg.sender][_spender] = _value;
    emit ERC20.Approval(msg.sender, _spender, _value);
     return true;
   }

  function allowance(address _owner, address _spender) public view returns (uint256) {
     return allowed[_owner][_spender];
   }


  //Admin can transfer his ownership to new address
  function transferownership(address _newaddress) public returns(bool){
      require(msg.sender==_admin);
      _admin=_newaddress;
      return true;
  }
    
}