LeetCode 961: N-Repeated Element in Size 2N Array Solution

Master LeetCode problem 961 (N-Repeated Element in Size 2N Array), a easy challenge, with our optimized solutions in Java, C++, and Python. Explore detailed explanations, test your code in our interactive editor, and prepare for coding interviews.

961. N-Repeated Element in Size 2N Array

Easy

Array Hash Table

Problem Explanation

Explanation:

We can solve this problem by using a hash set to keep track of unique elements encountered so far.
As we iterate through the array, if we encounter an element that already exists in the set, it means we have found the repeated element.
We return this repeated element as the final result.

Time Complexity: O(n)
Space Complexity: O(n)

Solution Code

class Solution {
    public int repeatedNTimes(int[] nums) {
        Set<Integer> set = new HashSet<>();
        for (int num : nums) {
            if (set.contains(num)) {
                return num;
            }
            set.add(num);
        }
        return -1; // Not found, should not reach here
    }
}

Try It Yourself

Loading code editor...

Frequently Asked Questions

How to solve LeetCode 961 (N-Repeated Element in Size 2N Array)?

This page provides optimized solutions for LeetCode problem 961 (N-Repeated Element in Size 2N Array) in Java, C++, and Python, along with a detailed explanation and an interactive code editor to test your code.

What is the time complexity of LeetCode 961 (N-Repeated Element in Size 2N Array)?

The time complexity for LeetCode 961 (N-Repeated Element in Size 2N Array) varies by solution. Check the detailed explanation section for specific complexities in Java, C++, and Python implementations.

Can I run code for LeetCode 961 on DevExCode?

Yes, DevExCode provides an interactive code editor where you can write, test, and run your code for LeetCode 961 in Java, C++, or Python.

Back to LeetCode Solutions