#include "bits/stdc++.h"

using namespace std;

signed main() {

	int n;
	cin >> n;
	int arr[10] = { 0 };
	for (int i = 0; i < n; i++) {
		int a, b, c, d;
		string mes;
		cin >> a >> b >> c >> d >> mes;
		if ("NO" == mes) {
			arr[a]++;
			arr[b]++;
			arr[c]++;
			arr[d]++;
		}
		else {
			for (int i = 0; i < 10; i++) {
				if (i == a)continue;
				if (i == b)continue;
				if (i == c)continue;
				if (i == d)continue;
				arr[i]++;
			}
		}
	}

	int ans;
	for (int i = 0; i < 10; i++) {
		if (0 == arr[i]) ans = i;
	}

	cout << ans << endl;

}