Problem 2: Contains Duplicate (easy)


This problem describes a coding challenge to determine if an integer array contains duplicate elements.
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Problem Statement

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.

Examples

Example 1:

Input: nums= [1, 2, 3, 4]
Output: false  
Explanation: There are no duplicates in the given array.

Example 2:

Input: nums= [1, 2, 3, 1]
Output: true  
Explanation: '1' is repeating.

Example 3:

Input: nums= [3, 2, 6, -1, 2, 1]
Output: true  
Explanation: '2' is repeating.

Constraints:

  • 1 <= nums.length <= 10^5
  • -10^9 <= nums[i] <= 10^9

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