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?
思路：异或！！
转载于:https://www.cnblogs.com/vincent93/p/6686612.html
