#include <bits/stdc++.h>
using namespace std;
int main() {
  string w = "hello", s;
  cin >> s;
  int j = 0;
  for (int i = 0; i < int(s.size()); ++i)
    if (s[i] == w[j]) ++j;
  cout << (j == 5 ? "YES" : "NO") << endl;
  return 0;
}
