MissingNumber.java

/*
Given an array nums containing n distinct numbers in the range [0, n], return the only number in the range that is missing from the array.
Example 1:
Input: nums = [3,0,1]
Output: 2
Explanation:
n = 3 since there are 3 numbers, so all numbers are in the range [0,3]. 2 is the missing number in the range since it does not appear in nums.

Example 2:
Input: nums = [0,1]
Output: 2
Explanation:
n = 2 since there are 2 numbers, so all numbers are in the range [0,2]. 2 is the missing number in the range since it does not appear in nums.
*/ 

class Solution {
    public int missingNumber(int[] nums) {
        int res[] = new int[nums.length + 1];
        for(int i = 0;i < nums.length;i++)
            res[nums[i]] = -1;
        int i;
        for(i = 0;i< res.length;i++){
            if(res[i] == 0) break;
        }
        return i;
    }
}