#include <bits/stdc++.h>
using namespace std;
inline long long sqr(long long x) { return x * x; }
mt19937 Random((int)time(0));
inline long long rnd(long long x) { return Random() % x; }
const long long INF = (long long)1e9 + 2018;
const long long MOD = (long long)1e9 + 7;
const long double PI = acos(-1.0);
pair<int, int> cnt(int n) {
  if (n & 1) {
    return {sqr(n / 2 + 1) + sqr(n / 2), n * n - sqr(n / 2 + 1) - sqr(n / 2)};
  } else {
    return {n * n / 2, n * n / 2};
  }
}
void $main() {
  int n;
  cin >> n;
  int a = 0, b = 0;
  for (int i = 0; i < n; i++) {
    string s;
    cin >> s >> s;
    a += s == "hard";
    b += s == "soft";
  }
  for (int i = 1;; i++) {
    pair<int, int> res = cnt(i);
    if ((res.first >= a && res.second >= b) ||
        (res.second >= a && res.first >= b)) {
      cout << i;
      return;
    }
  }
}
int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  cout.setf(ios_base::fixed, ios_base::floatfield);
  cout.precision(10);
  $main();
}
