python3

javascript

java

Missing Number II

Given an array `arr` containing `n` distinct numbers in the range `[0, n+1]`, return the only two numbers in the range that is missing from the array in **non-decreasing order**.

### Input Format
First parameter - number `n`

Second Parameter - array of integers `arr` of size `n`

### Output Format
Return the array

### Example 1
```
Input:
    5
    4 0 3 1 2
Output:
    5 6
Explanation:
    n = 5, so all numbers are in the range [0, 6]. 5 and 6 are the missing numbers in the range since they don't appear in the arr.
```

### Example 2
```
Input:
    8
    7 2 0 5 4 6 3 8
Output:
    1 9
Explanation:
    n = 8, so all numbers are in the range. 1 and 9 are the missing numbers in the range since they don't appear in the arr.
```

#### Constraints
- 1 <= n <= 10^4^
- 0 <= arr[i] <= (n+1)
- All the numbers of **arr** are **unique**.
- Expected Time complexity: O(n)
- Expected Space Complexity: O(1)

vector<int> solve(int n, vector<int> arr){
//CODE HERE 
}

static int[] solve(int n, int[] arr){
//CODE HERE 
}