#include <bits/stdc++.h>
using namespace std;
int main() {
  char str[120];
  int flag = 0, i = 0;
  cin >> str;
  while (str[i] != '\0') {
    while (str[i] != 'h' && str[i] != '\0') i++;
    if (str[i++] == 'h') flag++;
    while (str[i] != 'e' && str[i] != '\0') i++;
    if (str[i++] == 'e') flag++;
    while (str[i] != 'l' && str[i] != '\0') i++;
    if (str[i++] == 'l') flag++;
    while (str[i] != 'l' && str[i] != '\0') i++;
    if (str[i++] == 'l') flag++;
    while (str[i] != 'o' && str[i] != '\0') i++;
    if (str[i++] == 'o') flag++;
    i++;
  }
  if (flag >= 5)
    cout << "YES";
  else
    cout << "NO";
}
