#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  ;
  string s;
  cin >> s;
  int count = 0;
  for (int i = 0; i < s.size(); ++i) {
    if (s[i] == 'h' && count == 0)
      count++;
    else if (s[i] == 'e' && count == 1)
      count++;
    else if (s[i] == 'l' && (count == 2 || count == 3))
      count++;
    else if (s[i] == 'o' && count == 4)
      count++;
    if (count == 5) break;
  }
  if (count == 5)
    cout << "YES" << endl;
  else
    cout << "NO" << endl;
  return 0;
}
