#include<iostream>
using namespace std;
int main()
{
int arr[5][5],a=0,b=0,i,j,n;
cout<<"Enter size of matrix(max 5):";
cin>>n;
cout<<"Enter the matrix:\n";
for(i=0;i<n;++i)
for(j=0;j<n;++j)
cin>>arr[i][j];
for(i=0;i<n;++i)
for(j=0;j<n;++j)
if(j>i)
a+=arr[i][j];
else
if(i>j)
b+=arr[i][j];
cout<<"\nSum of elements above the diagonal:"<<a;
cout<<"\nSum of elements below the diagonal:"<<b;
return 0;
}
Output
Enter size of matrix(max 5):3
Enter the matrix:
1 2 3
4 5 6
3 0 2
Sum of elements above the diagonal:11
Sum of elements below the diagonal:7