#include <bits/stdc++.h>
using namespace std;
string s, hello = "hello!";
char x = 'h';
bool found_l = false;
int pos;
int main() {
  cin >> s;
  for (int i = 0; i < s.size() && hello[pos] != '!'; i++) {
    if (s[i] == x) x = hello[++pos];
  }
  if (x == '!')
    cout << "YES";
  else
    cout << "NO";
  return 0;
}
