Implement it on LeetCode. This should take just a few lines. Know the trade-off: the sorting approach uses O(1) extra space (if sorting in place) but O(nlogn) time. The hash set approach uses O(n) space but O(n) time. Interviewers may ask you about this trade-off.
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$ curl repovive.com/roadmaps/maang-interview-prep/arrays-hashing/contains-duplicate-implementation
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