[leetcode] problem 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.

Example

Input: [3,0,1]

Output: 2

Input: [9,6,4,2,3,5,7,0,1]

Output: 8

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

public int (int[] nums) {
    int result = 0;

    for (int i = 0; i < nums.length; i++)
        result ^= nums[i] ^ (i + 1);

    return result;
}