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Use a HashSet to detect duplicates quickly.
Example:
Input:
[1,2,3,1]Output:
trueCommon Mistakes:
- Off-by-one indexing
- Not handling edge cases (null/empty)
Notes:
Edge cases: duplicates, empty inputs, negative numbers where applicable.
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Use a HashSet to detect duplicates quickly.
Example:
Input:
[1,2,3,1]Output:
trueCommon Mistakes:
- Off-by-one indexing
- Not handling edge cases (null/empty)
Notes:
Edge cases: duplicates, empty inputs, negative numbers where applicable.
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Contains Duplicate