codingstuff.io
ExploreTutorialsProblemsCS Subjects
Get Started
ExploreTutorialsProblemsCS Subjects
Get Started
codingstuff.io

Master the art of building software through interactive tutorials, real-world problems, and guided projects.

Pune, Maharashtra, India

codingstuffmail@gmail.com

Product

  • Explore
  • Tutorials
  • Problems
  • CS Subjects

Company

  • About
  • Contact
  • Privacy Policy
  • Terms & Conditions
  • Sitemap

© 2026 codingstuff.io. All rights reserved.

Built with ❤️ for developers everywhere

ProblemsContains Duplicate

Contains Duplicate

Easy
ArraysHashing

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

Explanation:

The element 1 occurs at the indices 0 and 3.

Example 2:

Input: nums = [1,2,3,4]

Output: false

Explanation:

All elements are distinct.

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

Related Problems

View all
Two Sum
Easy•Arrays
Best Time to Buy and Sell Stock
Easy•Arrays
Product of Array Except Self
Medium•Arrays
Maximum Subarray
Medium•Arrays
Maximum Product Subarray
Medium•Arrays
Find Minimum in Rotated Sorted Array
Medium•Arrays
Input:
nums = [1,2,3,1]