#include <bits/stdc++.h>
using namespace std;
vector<char> helo;
bool used[10];
int main() {
  string s;
  cin >> s;
  string c = "hello";
  int ind = 0;
  for (int i = 0; i < 5; i++) {
    for (int j = ind; j < s.size(); j++) {
      if (c[i] == s[j]) {
        used[i] = 1;
        ;
        ind = j + 1;
        break;
      }
    }
  }
  int ans = 0;
  for (int i = 0; i < 5; i++)
    if (used[i]) ans++;
  if (ans == 5)
    cout << "YES";
  else
    cout << "NO";
}
