#+PROPERTY: STUDY_DECK_02
* TODO 0268. Missing Number :easy:
:PROPERTIES:
:NEETCODE: [[file:../../roadmap.org::*0268. Missing Number][0268. Missing Number]]
:END:

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 <= 10^{4}~

 - ~0 <= nums[i] <= n~

 - All the numbers of ~nums~ are *unique*.

*Follow up:* Could you implement a solution using only ~O(1)~ extra space complexity and ~O(n)~ runtime complexity?

** TODO Approach
Write your approach here.

** TODO Python
#+begin_src python
class Solution:
    def missingNumber(self, nums: List[int]) -> int:
#+end_src

** TODO C++
#+begin_src cpp
class Solution {
public:
    int missingNumber(vector<int>& nums) {
        
    }
};
#+end_src