If you just scramble a sentence, it's pretty useless because the recipients are never going to be able to reverse the process.

如果你只是加密一个句子，这是毫无用处的,因为收件人没法将这个句子,反加密出来。

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That can reverse the process.

都能以路径上的某个点表示）这是条可逆路径。

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