#include <bits/stdc++.h>
using namespace std;
int main() {
  int i = 0, j = 0;
  string str, temp = "hello";
  cin >> str;
  for (int j = 0; j < str.length(); j++) {
    if (str[j] == temp[i]) {
      i++;
    }
  }
  if (i == 5)
    cout << "YES";
  else
    cout << "NO";
  return 0;
}
