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