计算机联锁源代码，精品！对初学者很有用的，绝对值得一看！-Computer Interlocking source code, boutique! Very useful for beginners, and definitely worth a look!

互锁按钮，实现互锁，即A、B两个按钮同一时间内只有一个处于闭合状态，另一个反之。-Interlock button, to achieve interlock, ie A, B two buttons at the same time, only one closed and one hand.