#include <bits/stdc++.h>
using namespace std;
char a[101];
int n, m;
int main() {
  scanf("%s", a);
  {
    m = 0;
    n = strlen(a);
    for (int i = 0; i < n; i++) {
      if (m == 0 && a[i] == 'h')
        m = 1;
      else if (m == 1 && a[i] == 'e')
        m = 2;
      else if (m == 2 && a[i] == 'l')
        m = 3;
      else if (m == 3 && a[i] == 'l')
        m = 4;
      else if (m == 4 && a[i] == 'o')
        m = 5;
    }
    if (m == 5) {
      printf("YES");
    } else
      printf("NO");
  }
  return 0;
}
