#include <bits/stdc++.h>
using namespace std;

int main() {
  int N;
  cin >> N;
  vector<int> a(10, 0);
  for (int i = 0; i < N; i++) {
    int a1, a2, a3, a4;
    string s;
    cin >> a1 >> a2 >> a3 >> a4;
    cin >> s;
    if (s == "YES") {
      a[a1]++;
      a[a2]++;
      a[a3]++;
      a[a4]++;
    } else {
      a[a1]--;
      a[a2]--;
      a[a3]--;
      a[a4]--;
    }
  }
  sort(a.begin(), a.end());
  cout << a[9] << endl;
  return 0;
}