#include <bits/stdc++.h>
using namespace std;
int main() {
  int count = 0;
  char s[100];
  int i = 0;
  cin >> s;
  while (s[i] != '\0') {
    if (count == 0 && s[i] == 'h') {
      count++;
    } else if (count == 1 && s[i] == 'e') {
      count++;
    } else if (count == 2 && s[i] == 'l')
      count++;
    else if (count == 3 && s[i] == 'l')
      count++;
    else if (count == 4 && s[i] == 'o') {
      count++;
      break;
    }
    i++;
  }
  if (count == 5)
    cout << "YES" << endl;
  else
    cout << "NO" << endl;
}
