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.

代码如下：

 1 public class Solution {
 2     public int missingNumber(int[] nums) {
 3         Arrays.sort(nums);
 4         for(int i=0;i<nums.length;i++)
 5         {
 6             if(nums[i]!=i)
 7             return i;
 8         }
 9         return nums.length;
10     }
11 }