#include <bits/stdc++.h>
using namespace std;
int main() {
  char a[101];
  cin >> a;
  int p = 0;
  int q = 0;
  int r = 0;
  int s = 0;
  int t = 0;
  int l = 0;
  int m = 0;
  int n = 0;
  int o = 0;
  int k = 0;
  for (int i = 0; i < strlen(a); i++) {
    p++;
    if (a[i] == 'h') {
      ;
      k = 1;
      break;
    }
  }
  for (int i = p; i < strlen(a); i++) {
    q++;
    if (a[i] == 'e') {
      l = 1;
      break;
    }
  }
  for (int i = p + q; i < strlen(a); i++) {
    r++;
    if (a[i] == 'l') {
      m = 1;
      break;
    }
  }
  for (int i = p + q + r; i < strlen(a); i++) {
    s++;
    if (a[i] == 'l') {
      n = 1;
      break;
    }
  }
  for (int i = p + q + r + s; i < strlen(a); i++) {
    t++;
    if (a[i] == 'o') {
      o = 1;
      break;
    }
  }
  if (k == 1 && l == 1 && m == 1 && n == 1 && o == 1) {
    cout << "YES";
  } else {
    cout << "NO";
  }
}
