/* This program uses code from "Algorithms in C, Third Edition,"
 *               by Robert Sedgewick, Addison-Wesley, 1998.
 */

#include <stdlib.h>
#include <stdio.h>

#include "list_interface.h"


main(int argc, char ** argv)
{
   list the_list = newList();
   if (argc != 3)
   {
      printf("You need to provide two command line arguments: N and M.");
      return -1;
   }
    
   int N = atoi(argv[1]);
   int M = atoi(argv[2]);
   
   int i;
   link new_entry = newLink(1);
   setFirst(the_list, new_entry);
   link previous = new_entry;
   for (i = 2; i <= N; i++)
   {
      new_entry = newLink(i);
      insertLink(the_list, previous, new_entry);
      previous = new_entry;
   }
   
   /* make the list circular */
   link first_entry = listFirst(the_list);
   setNext(previous, first_entry);
   
   link current_link = previous;
   while(current_link != linkNext(current_link))
   {
      for (i = 1; i < M; i++)
      {
         current_link = linkNext(current_link);
      }
      link deleted = deleteNext(the_list, current_link);
      free(deleted);
   }
   
   first_entry = listFirst(the_list);
   printf("The chosen value is %d.\n", linkItem(first_entry));

   
   /* Before we destroy the list, we must make the first (and only remaining)
    * link point to NULL, otherwise destroyList will not work. */   
   setNext(first_entry, NULL);
   destroyList(the_list);
   return 0;
}