View Code of Problem 51

#include<iostream>
#include<string>
#include<algorithm>
using namespace std;
int a[10][10];
int main()
{
	int n;
	int sum=0;
	cin >> n;
	for (int i = 1; i <= n; i++)
	{
		for (int j = 1; j <= n; j++)
		{
			cin >> a[i][j];
		}
	}
	for (int i = 1; i <= n; i++)
	{
		for (int j = 1; j <= i; j++)
		{
			sum = sum + a[i][j];
		}
	}
	cout << sum;
	return 0;
	
}