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Curated IntersectionSheet: LeetCode Top Interview 150 Pattern: Hashmap Existence / Complement Lookup

LeetCode Top Interview 150 · Hashmap Existence / Complement Lookup

Use a hashmap or set purely to answer 'have I seen this before' or 'does the complement exist', not to count occurrences.

Sheet Problems: 5

Category: Hashing

Featured Problems (5)

1.Insert Delete GetRandom O(1)Medium

2.Valid SudokuMedium

4.Contains Duplicate IIEasy

5.Longest Consecutive SequenceMedium

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