#include <bits/stdc++.h>
using namespace std;
string s;
int x, q;
int main() {
  cin >> s;
  for (int i = 0; i < s.length(); i++) {
    q = 0;
    if (s[i] == 'h') {
      x = i;
      q = 1;
      break;
    }
  }
  if (q == 0) {
    cout << "NO" << endl;
    return 0;
  }
  for (int i = x + 1; i < s.length(); i++) {
    q = 0;
    if (s[i] == 'e') {
      x = i;
      q = 1;
      break;
    }
  }
  if (q == 0) {
    cout << "NO" << endl;
    return 0;
  }
  for (int i = x + 1; i < s.length(); i++) {
    q = 0;
    if (s[i] == 'l') {
      x = i;
      q = 1;
      break;
    }
  }
  if (q == 0) {
    cout << "NO" << endl;
    return 0;
  }
  for (int i = x + 1; i < s.length(); i++) {
    q = 0;
    if (s[i] == 'l') {
      x = i;
      q = 1;
      break;
    }
  }
  if (q == 0) {
    cout << "NO" << endl;
    return 0;
  }
  for (int i = x; i < s.length(); i++) {
    q = 0;
    if (s[i] == 'o') {
      x = i;
      q = 1;
      break;
    }
  }
  if (q == 0) {
    cout << "NO" << endl;
    return 0;
  }
  if (q == 1) {
    cout << "YES" << endl;
    return 0;
  }
  return 0;
}
