Contains Duplicate — Easy Coding Interview Question

Given an integer array nums, return true if any value appears at least twice in the array.

Example

Input: nums = [1,2,3,1]

Output: true

Constraints

• 1 ≤ nums.length ≤ 10⁵
• -10⁹ ≤ nums[i] ≤ 10⁹

Topics & Companies

Topics: arrays, hash-map

Asked by: Amazon, Google, Meta, Microsoft, Apple

Optimal Solution Complexity

Time complexity: O(n). Space complexity: O(n).

Practice more

• All DSA Problems
• DSA Patterns