石头、剪子、布：人和计算机各出其中一个，然后给出比较结果，接着重新进行比较，直到用户输入退出才结束。用多个函数实现。-Stone, scissors, cloth: and the computer from each one of them, and then gives results of the comparison, and then compare again until the user enters quit before the end. Achieved with multiple functions.