C++ :: Adding Up Elements Of Two Dimensional Array?

This code shows a loop inside a loop initializing a two-dimensional array named arr with elements [2] and [5]. Here's my code:

Code:
#include <iostream>
#include <conio.h>
using namespace std;
int main ()

[Code]....

Now, what I wanted to do is to have an output showing the sums of each elements. Example, the above code has an output of:

1 2 3 4 5
6 7 8 9 10

I wanted to have more codes which would add up the elements 1 + 6, 2 + 7, 3 + 8, 4 + 9, 5 + 10 and produce and output:

7 9 11 13 15