#include <bits/stdc++.h>
using namespace std;
int main() {
  string s, sub1, sub2;
  cin >> s;
  int arr[4];
  if (s.find('h') != -1 && s.find('e') != -1 && s.find('l') != -1 &&
      s.find('o') != -1) {
    arr[0] = s.find_first_of('h');
    arr[1] = s.find_last_of('o');
    sub1 = s.substr(arr[0], (arr[1] - arr[0]) + 1);
    if (sub1.find('e') != -1 && sub1.find('l') != -1) {
      arr[2] = sub1.find_first_of('e');
      arr[3] = sub1.find_last_of('l');
      sub2 = sub1.substr(arr[2], (arr[3] - arr[2]));
    } else {
      cout << "NO" << endl;
      return 0;
    }
    if (sub2.find('l') != -1)
      cout << "YES" << endl;
    else
      cout << "NO" << endl;
  } else
    cout << "NO" << endl;
  return 0;
}
