text: #include <stdio.h>
  #include <stdlib.h>
  #include "doublelist.h"
  
  int main()
  {
      No *lhead = NULL;
      insert_top(&lhead, 3);
      insert_top(&lhead, 2);
      insert_top(&lhead, 1);
      insert_top(&lhead, 0);
      insert_end(lhead, 4);
      print_list(lhead);
      printf("List size: %d\n", list_size(lhead));
      remove_top(&lhead);
      print_list(lhead);
      printf("List size: %d\n", list_size(lhead));
      remove_end(lhead);
      print_list(lhead);
      printf("List size: %d\n", list_size(lhead));
      remove_midle(lhead, 2);
      print_list(lhead);
      printf("List size: %d\n", list_size(lhead));
      insert_midle(lhead, 1, 2);
      print_list(lhead);
      printf("List size: %d\n", list_size(lhead));
      clear_list(&lhead);
      printf("List size: %d\n", list_size(lhead));
  
      return 0;
  }