#include <bits/stdc++.h>
using namespace std;
int main() {
  string str;
  string word = "hello";
  int k = 0;
  cin >> str;
  for (int idx = 0; idx < str.size(); idx++) {
    if (str[idx] == word[k]) {
      k++;
    }
  }
  if (k == 5) {
    cout << "YES" << endl;
  } else {
    cout << "NO" << endl;
  }
  return 0;
}
