contract BasicToken is ERC20 {
    using SafeMath for uint256;

    mapping(address => uint256) balances;
    mapping (address => mapping (address => uint256)) allowed;

    /**
  * @dev transfer token for a specified address
  * @param _to The address to transfer to.
  * @param _value The amount to be transferred.
  */

    function transfer(address _to, uint256 _value) returns (bool) {
        if (balances[msg.sender] >= _value && balances[_to] + _value > balances[_to]) {
            balances[msg.sender] = balances[msg.sender].sub(_value);
            balances[_to] = balances[_to].add(_value);
            Transfer(msg.sender, _to, _value);
            return true;
        }else {
            return false;
        }
    }
    

    /**
   * @dev Transfer tokens from one address to another
   * @param _from address The address which you want to send tokens from
   * @param _to address The address which you want to transfer to
   * @param _value uint256 the amout of tokens to be transfered
   */

    function transferFrom(address _from, address _to, uint256 _value) returns (bool) {
      if (balances[_from] >= _value && allowed[_from][msg.sender] >= _value && balances[_to] + _value > balances[_to]) {
        uint256 _allowance = allowed[_from][msg.sender];
        allowed[_from][msg.sender] = _allowance.sub(_value);
        balances[_to] = balances[_to].add(_value);
        balances[_from] = balances[_from].sub(_value);
        Transfer(_from, _to, _value);
        return true;
      } else {
        return false;
      }
}


    /**
  * @dev Gets the balance of the specified address.
  * @param _owner The address to query the the balance of. 
  * @return An uint256 representing the amount owned by the passed address.
  */

    function balanceOf(address _owner) constant returns (uint256 balance) {
    return balances[_owner];
  }

  function approve(address _spender, uint256 _value) returns (bool) {

    // To change the approve amount you first have to reduce the addresses`
    //  allowance to zero by calling `approve(_spender, 0)` if it is not
    //  already 0 to mitigate the race condition described here:
    //  https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
    require((_value == 0) || (allowed[msg.sender][_spender] == 0));

    allowed[msg.sender][_spender] = _value;
    Approval(msg.sender, _spender, _value);
    return true;
  }

  /**
   * @dev Function to check the amount of tokens that an owner allowed to a spender.
   * @param _owner address The address which owns the funds.
   * @param _spender address The address which will spend the funds.
   * @return A uint256 specifing the amount of tokens still avaible for the spender.
   */
  function allowance(address _owner, address _spender) constant returns (uint256 remaining) {
    return allowed[_owner][_spender];
  }

}
function transfer(address _to, uint256 _value) returns (bool) {
        if (balances[msg.sender] >= _value && balances[_to] + _value > balances[_to]) {
            balances[msg.sender] = balances[msg.sender].sub(_value);
            balances[_to] = balances[_to].add(_value);
            Transfer(msg.sender, _to, _value);
            return true;
        }else {
            return false;
        }
    }
/**
 * @dev transfer token for a specified address
 * @param _to The address to transfer to.
 * @param _value The amount to be transferred.
 */