View Code of Problem 51

#include <stdio.h>

int main() {
	int arr[10][10];
	int n;
	scanf("%d", &n);
	int i, j;
	for (i = 0; i < n; i++) {
		for (j = 0; j < n; j++) {
			scanf("%d", &arr[i][j]);
		}
	}
	int sum = 0;
	for (i = 0; i < n; i++) {
		for (j = 0; j <= i; j++) {
			sum += arr[i][j];
		}
	}
	printf("%d", sum);
}