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?

public class Solution {
    public int missingNumber(int[] nums) {
        int miss = -1;
        int n = nums.length;
        int sum = (n+1)*n/2;
        int s = 0;
        for(int i=0;i