# 136. Single Number(Solution || Leetcode easy || Java)

1 min readDec 19, 2022

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

**Constraints:**

`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.

# SOLUTION:

`class Solution {`

public int singleNumber(int[] nums) {

int ans = nums[0];

//If we Xor every number with each other then we will get the number

//that is repeated only in a single loop

for(int i = 1; i < nums.length; i++){

ans ^= nums[i];

}

return ans;

}

}

Runtime1 ms

Beats

100%

Memory50.7 MB

Beats

36.54%

Thank you for reading. If you have any queries then, please let me know in the comment section. I will surely be responsive toward it.