#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

int main() {
    int n;
    vector<vector<int>> yv;
    vector<int> nv;
    
    cin >> n >> std::ws;
    
    
    for (int i = 0; i < n; i++) {
        string tmps;
        vector<int> v;
        for (int j = 0; j < 5; j++) {
            cin >> tmps >> std::ws;
            if (tmps == "YES") {
                yv.push_back(v);
            } else if (tmps == "NO") {
                for (int k = 0; k < v.size(); k++){
                    nv.push_back(v[k]);
                }
            } else {
                v.push_back(stoi(tmps));
            }
        }
    }
    
    vector<int> base;
    for (int l = 0; l < 10; l++) {
        base.push_back(l);
    }
    
    vector<int> nnums;
    for (int m = 0; m < base.size(); m++) {
        int is_match = 0;
        for (int o = 0; o < nv.size(); o++) {
            if (base[m] == nv[o]) {
                is_match = 1;
            }
        }
        
        if (is_match == 0) {
            nnums.push_back(base[m]);
            
        }
    }
    
    if (nnums.size() != 1){
        for (int p = 0; p < yv.size(); p++) {
            vector<int> tmpv;
            for (int q = 0; q < nnums.size(); q++) {
                for (int r = 0; r < yv[p].size(); r++) {
                    if (nnums[q] == yv[p][r]) {
                        tmpv.push_back(nnums[q]);
                    }
                }
            }
            nnums = tmpv;
        }
    }    
    
    cout << nnums[0] << endl;
    
    return 0;
}