View Code of Problem 51

#include<iostream>
#include<string>
#include<cstring>
#include<vector>
#include<iomanip>
using namespace std;
int main()
{
	int n;
	cin >> n;
	int a[11][11];
	for (int i = 0;i < n;i++)
	{
		for (int j = 0;j < n;j++)
		{
			cin >> a[i][j];
		}
	}
	long long sum = 0;
	for (int i = 0;i < n;i++)
	{
		for (int j = 0;j <=i;j++)
		{
			sum += a[i][j];
		}
	}
	cout << sum;
}