Permutation in String

Given two strings s1 and s2, return true if s2 contains a permutation of s1, or false otherwise.

In other words, return true if some substring of s2 is an anagram of s1.

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Example 1

Input: s1 = "ab", s2 = "eidbaooo"
Output: true
Explanation: "ba" is a permutation of "ab" and appears as a substring of s2.

Example 2

Input: s1 = "ab", s2 = "eidboaoo"
Output: false
Explanation: No substring of s2 has exactly the same character counts as "ab".

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Constraints

• 1 <= s1.length, s2.length <= 10^4
• s1 and s2 consist of lowercase English letters.