Problem 2: Contains Duplicate (easy)

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Problem Description

The problem focuses on detecting duplicate integers within an input array. The function should return true if any integer appears more than once; otherwise, it returns false.

Examples

Several examples illustrate different scenarios:

[1, 2, 3, 4] returns false (no duplicates)
[1, 2, 3, 1] returns true (1 is duplicated)
[3, 2, 6, -1, 2, 1] returns true (2 is duplicated)

Constraints

The input array's length is constrained between 1 and 10⁵ elements (inclusive), and each integer within the array falls within the range of -10⁹ to 10⁹ (inclusive).

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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