#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define rep(i, n) for (int i = 0; i < (n); i++)
#define repr(i, n) for (int i = (n) - 1; i >= 0; i--)
#define range(a) a.begin(), a.end()

int main() {
  string S;
  cin >> S;
  int ans = 0;
  while (true) {
    string T;
    int i = 0;
    while (i < S.size()) {
      if (S.substr(i, 5) == "phnom") {
        ans++;
        i += 5;
        T += "penh";
      } else {
        T += S[i];
        i++;
      }
    }
    if (count(range(T), 'h') > 0 || count(range(T), 'e') > 0) {
      ans++;
      string U;
      for (char c : T) {
        if (c != 'h') {
          if (c == 'e') {
            U += 'h';
          } else {
            U += c;
          }
        }
      }
      T = U;
    } else break;
    S = T;
  }
  cout << ans << endl;
}