下面的表达式匹配所有小写字母和连字符。

The following expressions match all lowercase letters and the hyphen.

youdao

注意：要确定您可以找到指定术语的所有匹配项，并且由于这些术语对于底层字典是未知的，需要全部使用小写字母写入术语。

Note: To make sure, that you can find all occurrences of the specified terms, and because these terms are not known by the underlying dictionary, write the terms in all lower-case letters.

youdao

在方括号中，通过使用 -（连字符），比如 [a-z] 或者所有的小写字母，您可以引用某个范围的字符。

Within the brackets, you can refer to a range of characters by using - (hyphen), as in [a-z] or all lowercase letters.

youdao

You can brute force it and unfortunately, the so-called Caesar cipher is not very secure because if you assume, for our purposes in English alphabet with 26 characters, say all lowercase for all uppercase, my God, you only have to try like 24, 25, 26 possible rotations until you can figure out what his secret message is.

你可以强行解密但是不幸地是，所谓的凯撒密码不是很安全的,因为如果假设，对于我们的26个字符的字母表,指明所有的小写为大写，我的天，你只要试24，25次，26次就可以解答出,密文的内容。

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