Physical Address

304 North Cardinal St.
Dorchester Center, MA 02124

Single Number LeetCode Solution

Problem – Single Number

Given a non-empty array of integers nums, every element appears twice except for one. Find that single one.

You must implement a solution with a linear runtime complexity and use only constant extra space.

Example 1:

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

Example 2:

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

Example 3:

Input: nums = [1]
Output: 1


  • 1 <= nums.length <= 3 * 104
  • -3 * 104 <= nums[i] <= 3 * 104
  • Each element in the array appears twice except for one element which appears only once.

Single Number LeetCode Solution in C++

class Solution {
    int singleNumber(vector<int>& nums) { 
       unordered_map<int,int> a;
	   for(auto x: nums)
	   for(auto z:a)
			   return z.first;
	   return -1;

Single Number LeetCode Solution in Python

class Solution:
    def singleNumber(self, nums: List[int]) -> int:
        xor = 0
        for num in nums:
            xor ^= num
        return xor

Single Number LeetCode Solution in Java

public int singleNumber(int[] nums) {
    int ans =0;
    int len = nums.length;
    for(int i=0;i!=len;i++)
        ans ^= nums[i];
    return ans;
Single Number LeetCode Solution Review:

In our experience, we suggest you solve this Single Number LeetCode Solution and gain some new skills from Professionals completely free and we assure you will be worth it.

If you are stuck anywhere between any coding problem, just visit Queslers to get the Single Number LeetCode Solution

Find on LeetCode


I hope this Single Number LeetCode Solution would be useful for you to learn something new from this problem. If it helped you then don’t forget to bookmark our site for more Coding Solutions.

This Problem is intended for audiences of all experiences who are interested in learning about Data Science in a business context; there are no prerequisites.

Keep Learning!

More Coding Solutions >>

LeetCode Solutions

Hacker Rank Solutions

CodeChef Solutions

Leave a Reply

Your email address will not be published. Required fields are marked *