#include <bits/stdc++.h>

using namespace std;

int main() {
	int N; cin >> N;
	vector< vector<int> > v(N, vector<int>(4));
	vector<bool> r(N);
	for (int i = 0; i < N; ++i) {
		for (int j = 0; j < 4; ++j) {
			cin >> v[i][j];
		}
		string s; cin >> s;
		r[i] = s == "YES";
	}
	for (int i = 0; i < 10; ++i) {
		bool isAns = true;
		for (int j = 0; j < N; ++j) {
			bool f = false;
			for (int k = 0; k < 4; ++k) {
				if (v[j][k] == i) {
					f = true;
					break;
				}
			}
			if (f != r[j]) {
				isAns = false;
				break;
			}
		}
		if (isAns) {
			cout << i << endl;
			break;
		}
	}
}