#include <bits/stdc++.h>
using namespace std;
char s[256], v[] = {"hello"};
int n, nrh, nre, nrl, nro, ok, x, i;
int main() {
  cin.getline(s, 256);
  nrh = nre = nrl = nro = 0;
  ok = 0;
  x = 0;
  for (i = 0; i <= strlen(s); i++) {
    if (s[i] == 'h' && nrh < 1 && v[x] == 'h') {
      ok++;
      x++;
      nrh++;
    }
    if (s[i] == 'e' && nre < 1 && v[x] == 'e') {
      ok++;
      x++;
      nre++;
    }
    if (s[i] == 'l' && nrl < 2 && v[x] == 'l') {
      ok++;
      x++;
      nrl++;
    }
    if (s[i] == 'o' && nro < 1 && v[x] == 'o') {
      ok++;
      x++;
      nro++;
    }
  }
  if (ok == 5)
    cout << "YES";
  else
    cout << "NO";
  return 0;
}
