#include<iostream>
#include<bitset>
#include<string>
using namespace std;

int main(){
	int n, k;
	int b = 0, a;
	string s;
	for (int i = 0; i < 10; ++i) b |= (1 << i);
	cin >> n;
	for (int i = 0; i < n; ++i){
		a = 0;
		for (int i = 0; i < 4; ++i){
			cin >> k;
			a |= (1 << k);
		}
		cin >> s;
		if (s == "YES") b &= a;
		else b &= ~a;
	}
	for (int i = 0; i < 10; ++i){
		if (b & (1 << i)){
			cout << i << endl;
			break;
		}
	}
	return 0;
}