How to achieve matching in regular expressions

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Given a string (s) and a character pattern (p). Implement support for'.' Matches the regular expression of'*'.

'.' Matches any single character.' * 'matches zero or more preceding elements.

The match should cover the entire string (s), not part of the string.

Description:

S may be empty and contain only lowercase letters from amurz.

P may be empty and contain only lowercase letters from Amurz, as well as characters. And *.

Example 1:

Enter:

S = "aa" p = "a"

Output: false

Explanation: "a" does not match the entire string "aa".

Example 2:

Enter:

S = "aa" p = "a*"

Output: true

Explanation:'* 'means to match zero or more preceding elements, that is, to match' a'. Therefore, repeat'a 'once and the string can be changed to "aa".

Example 3:

Enter:

S = "ab" p = ". *"

Output: true

Explanation: ". *" means to match zero or more ('*') any character ('.').

Example 4:

Enter:

S = "aab" p = "c*a*b"

Output: true

Explanation:'c 'can not be repeated,' a 'can be repeated. So you can match the string "aab".

Example 5:

Enter:

S = "mississippi" p = "mis*is*p*."

Output: false above is all the content of the article "how to match regular expressions". Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!