#include <bits/stdc++.h>
using namespace std;
int main() {
  string hello = "hello";
  char ch;
  int i = 0;
  while (scanf("%c", &ch) && ch != '\n') {
    if (hello[i] == ch) {
      i++;
    }
  }
  cout << (i == 5 ? "YES" : "NO") << endl;
  return 0;
}
