#include <bits/stdc++.h>
using namespace std;
string s;
string h = "hello";
int j;
int buscar(char c, int idx) {
  for (int i = idx + 1; i < s.size(); i++) {
    if (c == s[i]) return i;
  }
  return -1;
}
int main() {
  cin >> s;
  int i = -1;
  for (; i < int(s.size()) - 1;) {
    int idx = buscar(h[j], i);
    if (idx != -1) {
      i = idx;
      j++;
    } else {
      cout << "NO";
      return 0;
    }
    if (j == 5) {
      cout << "YES";
      return 0;
    }
  }
  cout << "NO";
}
