#include <bits/stdc++.h>
using namespace std;
int main() {
  string s, a;
  cin >> s;
  a = s;
  int x = 0;
  int i, j, k, m, n;
  for (i = 0; i < s.size(); i++) {
    if (a[i] == 'h') {
      x++;
      break;
    }
  }
  for (j = i + 1; j < s.size(); j++) {
    if (a[j] == 'e') {
      x++;
      break;
    }
  }
  for (k = j + 1; k < s.size(); k++) {
    if (a[k] == 'l') {
      x++;
      break;
    }
  }
  for (m = k + 1; m < s.size(); m++) {
    if (a[m] == 'l') {
      x++;
      break;
    }
  }
  for (n = m + 1; n < s.size(); n++) {
    if (a[n] == 'o') {
      x++;
      break;
    }
  }
  if (x == 5)
    cout << "YES";
  else
    cout << "NO";
  return 0;
}
