function transfer(address _to, uint256 _value)
        public
    returns ( bool ) {
        require(tokenState == true);
        require(_to != address(0));
        require(_value <= balances[msg.sender]);
        require(blockState == false);
        require(userBanned[msg.sender] == false);
        balances[msg.sender] = sub(balances[msg.sender],_value);
        balances[_to] = add(balances[_to],_value);
        Transfer(msg.sender, _to, _value);
        return true;
    }