Given 2 sorted arrays Ar1 and Ar2 of size N each. Merge the given arrays and find the sum of the two middle elements of the merged array.

Given 2 sorted arrays Ar1 and Ar2 of size N each. Merge the given arrays and find the sum of the two middle elements of the merged array.

Example 1:

Input:
N = 5
Ar1[] = {1, 2, 4, 6, 10}
Ar2[] = {4, 5, 6, 9, 12}
Output: 11
Explanation: The merged array looks like
{1,2,4,4,5,6,6,9,10,12}. Sum of middle
elements is 11 (5 + 6).

Example 2:

Input:
N = 5
Ar1[] = {1, 12, 15, 26, 38}
Ar2[] = {2, 13, 17, 30, 45}
Output: 32
Explanation: The merged array looks like
{1, 2, 12, 13, 15, 17, 26, 30, 38, 45} 
sum of middle elements is 32 (15 + 17).

Your Task:
You don’t need to read input or print anything. Your task is to complete the function findMidSum() which takes ar1, ar2 and n as input parameters and returns the sum of middle elements.

Expected Time Complexity: O(log N)
Expected Auxiliary Space: O(1)

Constraints:
1 <= N <= 103
1 <= Ar1[i] <= 106
1 <= Ar2[i] <= 106

Solution:

//Given 2 sorted arrays Ar1 and Ar2 of size N each. Merge the given arrays and find the sum of the two middle elements of the merged array.
func sumOfSortedArray(Ar1:[Int], Ar2:[Int],N:Int)->Int{
var newArray = [Int]()
newArray.append(contentsOf: Ar1)
newArray.append(contentsOf: Ar2)
newArray = newArray.sorted()
//this is how we can get middle index by total of both array divided by 2 and need to minus 1 because array always start with 0 not 1.
let middleElementIndex = ((N+N)/2) - 1
let sum = newArray[middleElementIndex] + newArray[middleElementIndex + 1]
print(sum)
return sum
}