#include <bits/stdc++.h>
using namespace std;
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) begin(v),end(v)
template<typename A, typename B> inline bool chmax(A & a, const B & b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A & a, const B & b) { if (a > b) { a = b; return true; } return false; }
using ll = long long;
using pii = pair<int, int>;
constexpr ll INF = 1ll<<30;
constexpr ll longINF = 1ll<<60;
constexpr ll MOD = 1000000007;
constexpr bool debug = false;
//---------------------------------//

int main() {
	int N;
	cin >> N;
	vector<int> A(N), B(N), C(N), D(N);
	vector<string> R(N);
	REP(i, N) cin >> A[i] >> B[i] >> C[i] >> D[i] >> R[i];
	REP(i, 10) {
		bool ok = true;
		
		REP(j, N) {
			bool cur = A[j] == i || B[j] == i || C[j] == i || D[j] == i;
			if (cur ^ (R[j] == "YES")) ok = false;
		}
		
		if (ok) {
			cout << i << endl;
			return 0;
		}
	}
}