View Code of Problem 51

#include <stdio.h>
int main()
{
    int i,j,n;
    int a[100][100];
    int sum=0;
    scanf("%d",&n);
    for (i=0; i<n; i++)
    {
        for (j=0; j<n; j++)
        {
            scanf("%d",&a[i][j]);
        }
    }
    for (i=0; i<n; i++)
    {
        for (j=0; j<=i; j++)
        {
            sum+=a[i][j];
        }
    }
    printf("%d",sum);
    return 0;
}