#include <string>
#include <iostream>
using namespace std;
int main() {
	string s;
	cin >> s;
	int ans = 0;
	while (true) {
		if (s.find("phnom") != string::npos) {
			string nxt;
			int pos = 0;
			while (pos < s.size()) {
				if (s.substr(pos, 5) == "phnom") {
					nxt += "penh";
					pos += 5;
				}
				else {
					nxt += s[pos];
					pos += 1;
				}
			}
			s = nxt;
		}
		else if (s.find('h') != string::npos || s.find('e') != string::npos) {
			string nxt;
			for (int i = 0; i < s.size(); ++i) {
				if (s[i] == 'e') nxt += 'h';
				else if (s[i] != 'h') nxt += s[i];
			}
			s = nxt;
		}
		else break;
		++ans;
	}
	cout << ans << endl;
	return 0;
}