I think it depends on whether the list is odd or even in length. Actually, that's probably not true. With one, it'll probably always get it down there, but if I've made it just equal to two I might have lost.

是奇数还是偶数，事实上,这是不正确的，如果最后剩下一个,那可能得到了结果,如果剩下两个，可能错了,所以，首先我们要格外。

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