可以被4整除的二进制数的正则表达式

Question

I want to create a regular expression to match the following: 我想创建一个正则表达式来匹配以下内容：

L : the set of all bit strings (ie strings over alphabet {0,1} ) that are divisible by 4 L ：可被4整除的所有位字符串（即字母{0,1}字符串）的集合

Answer 1

If a binary is divisible by four, the last two bits are zero. 如果二进制可被四整除，则最后两位为零。 So you can use this Regex to match: 因此，您可以使用此正则表达式进行匹配：

/.+00$/

or, if you want to check that it is indeed a binary number (only zeros and ones), you can use: 或者，如果您要检查它确实是一个二进制数（仅是零和一），则可以使用：

/[01]+00$/

If you also want to match 0 and 00 : 如果您还想匹配0和00 ：

/^(00?|[01]+00)$/

if you don't want to match all zeros, you can use: 如果您不想匹配所有零，则可以使用：

/(?=1)[01]+00$/