268. Missing Number

Given an array containing n distinct numbers taken from 0, 1, 2, ..., n, find the one that is missing from the array.

For example,
Given nums = [0, 1, 3] return 2.

Note:
Your algorithm should run in linear runtime complexity. Could you implement it using only constant extra space complexity?

Similar:

41. First Missing Positive

136. Single Number

287. Find the Duplicate Number

public class Solution {
    public int missingNumber(int[] nums) {
        int xor = 0;
        for (int i = 0; i < nums.length; i++) {
            xor ^= i ^ nums[i];
        }
        xor ^= nums.length;
        return xor;
    }
}