Leetcode Single number C + + ideas for solving problems

Title Description:

Given an array of integers, every element appears twice except for one. Find the single one.

Note:
Your algorithm should has a linear runtime complexity. Could you implement it without using extra memory?

Requires linear complexity and no additional storage space.

I did not think about it, and learned the other people in the discuss method.

Initialize an int num=0, and then use this num and each number in the array to be different or over again, because the two same number XOR will become 0, so the traversal to the end is 0 and that individual number XOR, the result is that individual number, notice that 0 and 0 xor or 0, so initialize to 0.

The code is as follows:

int singlenumber (intint  n) {    int0;      for (int0; i < n; i++)         ^=a[i];     return num;}

Leetcode Single number C + + ideas for solving problems