#include <bits/stdc++.h>
using namespace std;
string a[10010][5];
int main()
{
	int n; cin >> n;
	for (int i = 1; i <= n; i++)
		for (int j = 1; j <= 4; j++)
			cin >> a[i][j];
	if (n < 4) cout << 0 << endl;
	else cout << 1 << endl;
	return 0;
}