#include <algorithm>
#include <iostream>
#include <cstdio>
#include <map>
#include <numeric>
#include <cmath>
#include <set>
#include <sstream>
#include <string>
#include <vector>
#include <queue>
#include <complex>
#include <string.h>
#include <unordered_set>
#include <unordered_map>
#include <iomanip>
using namespace std;

#define endl '\n'
#define all(v) (v).begin(), (v).end()
#define rall(v) (v).rbegin(), (v).rend()
#define uniq(v) (v).erase(unique((v).begin(), (v).end()), (v).end())

typedef long long ll;
typedef pair<int, int> P;
typedef unsigned int uint;
typedef unsigned long long ull;
struct pairhash {
public:
    template<typename T, typename U>
    size_t operator()(const pair<T, U> &x) const {
	size_t seed = hash<T>()(x.first);
	return hash<U>()(x.second) + 0x9e3779b9 + (seed<<6) + (seed>>2);
    }
};

const int inf = 1000000009;

string to_binString(int val) {
    if (!val)
	return string("0");

    string ret;
    while(val != 0) {
	if ((val & 1) == 0)
	    ret.insert(ret.begin(), '0');
	else
	    ret.insert(ret.begin(), '1');
	val >>= 1;
    }
    return ret;
}


int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout << fixed << setprecision(15);

    int n;
    cin >> n;
    int v[4];
    int bit = (1<<10)-1;
    for (int i = 0; i < n; i++) {
	for (int j = 0; j < 4; j++) cin >> v[j];
	string s;
	cin >> s;
	int b = 0;
	for (int i = 0; i < 4; i++) b |= (1<<v[i]);
	if (s == "NO") {
	    b = ~b;
	}
	bit &= b;
    }
    for (int i = 0; i < 10; i++) {
	if ((bit>>i)&1) {
	    cout << i << endl;
	    break;
	}
    }
}