	function transfer(address _recipient, uint _value) public onlyPayloadSize(2*32) {
	    require(balances[msg.sender] >= _value && _value > 0);
	    balances[msg.sender] = balances[msg.sender].sub(_value);
	    balances[_recipient] = balances[_recipient].add(_value);
	    emit Transfer(msg.sender, _recipient, _value);
    }