View Code of Problem 51

#include <stdio.h>
#include <stdlib.h>
  
int main()
{
    int n,i,j,sum=0;
    while(scanf("%d",&n)!=EOF){
    	sum = 0;
    int a[n+1][n+1];                   
    for(i=1;i<=n;i++)
        for(j=1;j<=n;j++)
            scanf("%d",&a[i][j]);       
    for(i=1;i<=n;i++)
        for(j=1;j<=i;j++)
        sum+=a[i][j];                   
    printf("%d\n",sum); 
}
    return 0;
}