#include <bits/stdc++.h>
using namespace std;
int main() {
  char s[105];
  int i, c = 0;
  cin >> s;
  for (i = 0; i < strlen(s); i++) {
    if (c == 0 && s[i] == 'h')
      c++;
    else if (c == 1 && s[i] == 'e')
      c++;
    else if (c == 2 && s[i] == 'l')
      c++;
    else if (c == 3 && s[i] == 'l')
      c++;
    else if (c == 4 && s[i] == 'o')
      c++;
  }
  if (c == 5)
    cout << "YES" << endl;
  else
    cout << "NO" << endl;
  return 0;
}
