#include <bits/stdc++.h>
using namespace std;
map<int, int> M;
vector<string> dan(5);
int main() {
  string s, s1, s2;
  getline(cin, s);
  int pos = 0;
  s1 = "hello";
  for (int i = 0; i < s.length(); i++)
    if (s[i] == s1[pos]) {
      pos++;
      if (pos == 5) {
        cout << "YES";
        return 0;
      }
    }
  cout << "NO";
  return 0;
}
