View Code of Problem 51

#include <stdio.h>

int main() {
	int size, sum = 0, temp;
	scanf("%d", &size);
	for(int i=0; i<size; i++) {
		for(int j=0; j<size; j++ ) {
			scanf("%d", &temp);
			if(j <= i) {
				sum += temp;
			}
		}
	}
	printf("%d\n", sum);

	return 0;
}