Single Number - Leetcode

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

Example 1:
Input: [2,2,1]
Output: 1
 
Example 2:
Input: [4,1,2,1,2]
Output: 4
 
 
class Solution {
    public int singleNumber(int[] nums) {
       
         int result = 0;
         for(int i : nums) {
           result ^= i;
           }
    return result; 
}
} 

Here we are going to do XOR operation. Because each number in array is repeated twice. So, XOR of same number is always 0 and  number which is not repeated will be stored in result.
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