View Code of Problem 51

#include <stdio.h>

int main(){
	int n;
	scanf("%d",&n);
	int i,j;
	int a[n][n];
	for(i=0;i<n;i++){
		for(j=0;j<n;j++){
			scanf("%d",&a[i][j]);
		}
	}
	
	int sum=0;
	
	for(i=0;i<n;i++){
		for(j=0;j<=i;j++){
			sum+=a[i][j];
		}
	}
	
	printf("%d",sum);
}