Contains Duplicate
Easy
Array
Hash Table
Sorting
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.
Example 1
Input: nums = [1,2,3,1]
Output: true
Example 2
Input: nums = [1,2,3,4]
Output: false
Example 3
Input: nums = [1,1,1,3,3,4,3,2,4,2]
Output: true

Constraints

  • •1 <= nums.length <= 10⁵
  • •-10⁹ <= nums[i] <= 10⁹
Time Complexity
O(n)
Space Complexity
O(n)
14
Case 1
Input: [1,2,3,1]
Expected: true
Case 2
Input: [1,2,3,4]
Expected: false