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