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Curated IntersectionSheet: NeetCode All Pattern: Hashmap Existence / Complement Lookup

NeetCode All · 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: 6

Category: Hashing

Featured Problems (6)

1.Contains DuplicateEasy

3.Valid SudokuMedium

4.Longest Consecutive SequenceMedium

5.Insert Delete GetRandom O(1)Medium

6.Contains Duplicate IIEasy

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