Permutation In String
Detailed guide and Python implementation for the 'Permutation In String' problem.
Problem Statement
Given two strings s1 and s2, return True if s2 contains a permutation of s1, or False otherwise.
In other words, return True if one of s1's permutations is a substring of s2.
Write a function checkInclusion(s1: str, s2: str) -> bool.
- •1 <= len(s1), len(s2) <= 10^4
- •s1 and s2 consist of lowercase English letters
Examples
s1 = "ab", s2 = "eidbaooo"
True
s2 contains one permutation of s1: "ba" (starting at index 3).
s1 = "ab", s2 = "eidboaoo"
False
No permutation of "ab" exists as a contiguous substring in s2.
Need a Hint?
Edge Cases to Watch
- Empty input structures
- Single element inputs
- Large numerical bounds
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