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

int main() {
    int n;
    cin >> n;
    set<int> no;
    vector<pair<pair<int, int>, pair<int, int>>> val;
    
    for (int i = 0; i < n; i++) {
        int a, b, c, d;
        string s;
        cin >> a >> b >> c >> d >> s;
        if (s == "YES") {
            val.emplace_back(make_pair(a, b), make_pair(c, d));
        } else {
            for (int e : {a, b, c, d}) no.emplace(e);
        }
    }
    
    int ans = 0;
    for (int i = 0; i < 10; i++) {
        if (no.count(i)) continue;
        bool ok = true;
        for (const auto &e : val) {
            int a, b, c, d;
            tie(a, b) = e.first;
            tie(c, d) = e.second;
            ok &= (a == i or b == i or c == i or d == i);
        }
        if (ok) { ans = i; break; }
    }
    
    cout << ans << '\n';
    return 0;
}