function withdraw() external onlyOwner returns (bool success) {        
        uint256 N = 1;
        if (block.timestamp > start) {
            N = (block.timestamp - start) / period;
        }

        if (!AlreadyReward[N]) {
            uint amount = reward[N];
            AlreadyReward[N] = true;
            msg.sender.transfer(amount);
            emit withdrawProfit(amount, msg.sender);
            return true;
        } else {
            return false;
        }
    }