#include <bits/stdc++.h>
using namespace std;
int main() {
  string s, temp = "hello";
  cin >> s;
  int j = 0;
  for (int i = 0; i < s.length(); i++) {
    if (s[i] == temp[j]) {
      j++;
    }
    if (j == 5) {
      cout << "YES";
      break;
    }
  }
  if (j != 5) cout << "NO";
  return 0;
}
