#include<sstream>
#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<string>
#include<vector>
#include<set>
#include<map>
#include<queue>
#include<numeric>
#include<functional>
#include<algorithm>
#include<bitset>
using namespace std;
#define INF (1<<29)
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define all(v) v.begin(),v.end()
#define uniq(v) v.erase(unique(all(v)),v.end())
#define indexOf(v,x) (find(all(v),x)-v.begin())




int main(){
	int yes=2047,no=0;
	int n;
	cin>>n;
	rep(i,n){
		int a,b,c,d;
		string r;
		cin>>a>>b>>c>>d>>r;
		int m=1<<a|1<<b|1<<c|1<<d;
		if(r=="YES"){
			yes&=m;
		}else{
			no|=m;
		}
	}
	rep(i,11){
		if((yes>>i&1)==1 && (no>>i&1)==0){
			cout<<i<<endl;
			break;
		}
	}
	return 0;
}