#include <bits/stdc++.h>
using namespace std;

int main() {
	int N;
	cin >> N;
	
	vector<int> vec_n(10); //NGのflag管理
	vector<int> vec_o(10); //OKのflag管理
	
	for(int a=0; a < N; a++){
		int v1,v2,v3,v4;
		string s;
		cin >> v1 >> v2 >> v3 >> v4 >> s;
		
		if(s == "YES"){
			vec_o.at(v1) = 1;
			vec_o.at(v2) = 1;
			vec_o.at(v3) = 1;
			vec_o.at(v4) = 1;
		}
		else{
			vec_n.at(v1) = 1;
			vec_n.at(v2) = 1;
			vec_n.at(v3) = 1;
			vec_n.at(v4) = 1;
		}
	}
	
	for(int b=0; b < 10; b++){
		if(vec_o.at(b) == 1 && vec_n.at(b) == 0){
			cout << b << endl;
			return 0;
		}
	}
	
}