function transfer(address to, uint value)public returns (bool ok);
  event Transfer(address indexed from, address indexed to, uint value);
  event Approval(address indexed owner, address indexed spender, uint value);
}


contract TRIPAGO is ERC20
{ using SafeMath for uint256;
    
    string public constant name = "TRIPAGO";

    
    string public constant symbol = "TPG";
    uint8 public constant decimals = 18;
    uint public _totalsupply = 1000000000 * 10 ** 18; 
    address public owner;                    
    uint256 public _price_tokn; 
    uint256 no_of_tokens;
    uint256 public pre_startdate;
    uint256 public ico_startdate;
    uint256 public pre_enddate;
    uint256 public ico_enddate;
    bool stopped = false;
   
    mapping(address => uint) balances;
    mapping(address => mapping(address => uint)) allowed;
     address ethFundMain = 0x85B442dBD198104F5D43Fbe44F9F8047D9D3705F; 

    
     enum Stages {
        NOTSTARTED,
        PRESALE,
        ICO,
        ENDED
    }