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

Palakkgoyal
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.

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Palakkgoyal

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