#include "bits/stdc++.h"
using namespace std;
using Graph = vector<vector<int>>;
typedef long long ll;
typedef pair<ll, ll> P;
#define rep(i,n) for (ll i = 0; i < (n); ++i)
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
const long long mod = 1e9 + 7;

ll gcd(ll a, ll b) {
	return b ? gcd(b, a % b) : a;
}

ll lcm(ll a, ll b) {
	return a / gcd(a, b) * b;
}

int main() {
	ll n;
	cin >> n;
	
	vector<bool> v(10, true);

	rep(i, n) {
		ll a,b,c,d;
		string s;
		cin >> a >> b >> c >> d >> s;
		if (s == "YES") {
			rep(j, 10) {
				if (j != a && j != b && j != c && j != d) {
					v[j]=false;
				}
			}
		} else {
			v[a] = false;
			v[b] = false;
			v[c] = false;
			v[d] = false;
		}
	}

	rep(i, 10) {
		if (v[i]) {
			cout << i << endl;
			return 0;
		}
	}

}