#include <bits/stdc++.h>

using namespace std;

int main() {
    int n;
    cin >> n;
    set<int> st{0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
    for (int i = 0; i < n; i++) {
        int a, b, c, d;
        string r;
        cin >> a >> b >> c >> d >> r;
        if (r == "YES") {
            for (int j = 0; j < 10; j++) {
                if (j != a && j != b && j != c && j != d) {
                    st.erase(j);
                }
            }
        } else {
            st.erase(a);
            st.erase(b);
            st.erase(c);
            st.erase(d);
        }
    }
    cout << *st.begin() << endl;
    return 0;
}