missing-number.js

// Missing Number

// 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.
// Example 3:

// Input: nums = [9,6,4,2,3,5,7,0,1]
// Output: 8
// Explanation: n = 9 since there are 9 numbers, so all numbers are in the range [0,9]. 8 is the missing number in the range since it does not appear in nums.
 

// Constraints:

// n == nums.length
// 1 <= n <= 104
// 0 <= nums[i] <= n
// All the numbers of nums are unique.



 var missingNumber = function(nums) {
    let map  = new Set(nums)
    for(let i = 0; i < nums.length + 1; i++){
        if (!map.has(i)){
            return i
        }
    }
};