#include <bits/stdc++.h>
using namespace std;
int main() {
  int i = 0;
  char a;
  char A[] = "hello";
  while (cin >> a && a != '\n') {
    if (a == A[i]) i++;
  }
  if (i == 5)
    cout << "YES" << endl;
  else
    cout << "NO" << endl;
}
