#include <bits/stdc++.h>
using namespace std;
int main() {
  long int n, i, f, j;
  j = 0;
  f = 0;
  string st;
  cin >> st;
  n = st.size();
  string J = "hello";
  for (i = 0; i < n; i++) {
    if (st[i] == J[j]) j++;
    if (j == 5) {
      f = 1;
      break;
    }
  }
  if (f == 1)
    cout << "YES";
  else
    cout << "NO";
  return 0;
}
