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