#include <vector>
#include <string>
#include <algorithm>
#include <numeric>
#include <iostream>
#include <cstdlib>
#include <cstring>
#include <utility>
#include <list>
#include <map>
#include <set>
#include <queue>
#include <iterator>
#include <cmath>
#include <iomanip>
using namespace std;

using ull = unsigned long long;
using ll = long long;

int main()
{
    int n;
    cin >> n;

    set<int> ans = {0,1,2,3,4,5,6,7,8,9};

    for(int i = 0; i < n; ++i)
    {
        int a,b,c,d;
        cin >> a >> b >> c >> d;
        string res;
        cin >> res;

        if(res == "YES")
        {
            for(int i =0; i < 10; ++i)
            {
                if(a == i || b == i || c == i || d == i)    continue;
                ans.erase(i);
            }
        }
        else
        {
            ans.erase(a);
            ans.erase(b);
            ans.erase(c);
            ans.erase(d);
        }
    }

    cout << *(ans.begin()) << endl;
}