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Contains Duplicate

Easy

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Given an integer array nums, return true if any value appears at least twice in the array, and return false if every element is distinct.

Sample Input:

[1, 2, 3, 1]

Sample Output:

true

Hints

Hint 1

Use a Set to track seen numbers

Hint 2

If a number is already in the set, return true

Hint 3

Return false if no duplicates found

Code Editor

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