#include <bits/stdc++.h>
using namespace std;
auto SOLUTION_FUNCTION(void) -> void {
  bool e(false), l(false), o(false), done(false);
  int lc = 0;
  string s;
  cin >> s;
  for (int i = 0; i < s.size(); ++i) {
    if (done) {
      continue;
    }
    if (s[i] == 'h') {
      e = true;
      continue;
    }
    if (s[i] == 'e' and e) {
      l = true;
      continue;
    }
    if (s[i] == 'l' and lc <= 2 and l) {
      lc++;
      if (lc >= 2) {
        o = true;
      }
      continue;
    }
    if (s[i] == 'o' and o) {
      done = true;
    }
  }
  puts((done) ? "YES" : "NO");
  return;
}
int main(void) {
  ios::sync_with_stdio(false);
  cin.tie(nullptr);
  cout.tie(nullptr);
  cout << setprecision(10);
  cout << fixed;
  cout << boolalpha;
  int testcase = 1;
  while (testcase--) {
    SOLUTION_FUNCTION();
  }
  return 0;
}
