mediumNeetCode 150
Permutation in String
Check if s2 contains a permutation of s1 Example: s1 = "ab", s2 = "eidbaooo" => true (contains "ba")
Permutation in String is less about the final answer and more about disciplined window bookkeeping. Interviewers love it because it reveals your stateful scanning and your edge-case discipline. Be disciplined about counts and boundaries; most bugs are off-by-one window moves.
Arrays & HashingSliding WindowStringTwo Pointers
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1Part 1: Permutation in Stringmedium
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Based onLeetCode