#include <iostream>
#include <cstdio>
#include <vector>
#include <algorithm>
#include <utility>
#include <string>

using namespace std;

int main() {
	int n;

	cin >> n;

	int a, b, c, d;
	string r;

	int stat[10] = {0};
	int mask = (1 << 10) - 1;
	int ansbit = mask;

	for (int i = 0; i < n; i++) {
		cin >> a >> b >> c >> d >> r;

		int stat = (1 << a) | (1 << b) | (1 << c) | (1 << d);

		if (r == "NO") {
			stat = ~stat & mask;
		}
		ansbit &= stat;
	}

	for (int i = 0; i < 10; i++) {
		if ((ansbit >> i) & 1) {
			cout << i << endl;
			break;
		}
 	}

	return 0;
}