#include <bits/stdc++.h>
using namespace std;
int main() {
  char a[] = "hello";
  char c;
  int i = 0;
  while (scanf("%c", &c) == 1) {
    if (c == a[i]) i++;
  }
  if (i == 5)
    cout << "YES";
  else
    cout << "NO";
  return 0;
}
