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Curated IntersectionSheet: NeetCode 150Pattern: Hashmap Existence / Complement Lookup

NeetCode 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: 4
Category: Hashing

Featured Problems (4)

1.Contains DuplicateEasy
Solve
2.Two SumEasy
Solve
3.Valid SudokuMedium
Solve
4.Longest Consecutive SequenceMedium
Solve

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