You rotate the letters by a deterministic amount, by a fixed number of steps so that the end result is actually something that can be reversed.

你用确定的数量旋转那些字母，通过一个固定数量的步骤,这样，最终结果是可以把它,反加密出来。

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So in this case, it just keeps chopping down from the back end, which kind of makes sense, all right? But in a fixed number, in fact, twenty-three calls, it gets down to the point of being able to say whether it's there.

所以在这个例子中,我们能理解他从后端开始排除元素，这，里事实上每次会确定的运行23次，找到最终的元素,我们来换个方向，对。

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