#include <bits/stdc++.h>
using namespace std;
int main() {
  string s;
  cin >> s;
  int c = 0;
  for (int i = 0; i < s.size(); i++) {
    if (c == 0 && s[i] == 'h')
      c = 1;
    else if (c == 1 && s[i] == 'e')
      c = 2;
    else if (c == 2 && s[i] == 'l')
      c = 3;
    else if (c == 3 && s[i] == 'l')
      c = 4;
    else if (c == 4 && s[i] == 'o') {
      c = 5;
      break;
    }
  }
  if (c == 5)
    cout << "YES\n";
  else
    cout << "NO\n";
}
