import java.io.*;

public class MoveMain
{
	public static void main (String[ ] args)
	{		
		final int SENTINEL = -1;

		final String PROMPT = "\nPlease enter a non-negative integer or " + 
					    SENTINEL + " to quit: ";

		final String ERROR = "Error: the input must be a non-negative integer or " 
					   + SENTINEL;

		final String MESSAGE = " disk(s) can be moved from pole A to pole B " +
                                   "in the following step(s):\n\n";

		BufferedReader reader = new BufferedReader (new InputStreamReader (System.in));

		int n;

		while (true)
		{
			try
			{
				System.out.print (PROMPT);
				n = Integer.parseInt (reader.readLine());
				if (n == SENTINEL)
					break;								
				System.out.println (n + MESSAGE + move (n, 'A', 'B', 'C'));
			} // try
			catch (Exception e)
			{
				System.out.println (e);
			} // catch
		} // while		
	} // method main

      /**
       * Determines the steps needed to move disks from an origin to a destination.
       *                        n
       * The worstTime(n) is O(2 ).
       * 
       * @param n the number of disks to be moved.
       * @param orig the pole where the disks are originally.
       * @param dest the destination pole
       * @param temp the pole used for temporary storage.
       * 
       * @return a String representation of the moves needed.
       * 
       * @throws IllegalArgumentException if n is less than or equal to 0.
       */    
      public static String move (int n, char orig, char dest, char temp) 
      {
      	final String DIRECT_MOVE = 
		"Move disk " + n + " from " + orig + " to " + dest + "\n";

       	if (n <= 0)
              	throw new IllegalArgumentException( );
       	if (n == 1)
             	return DIRECT_MOVE;
       	String result = move (n - 1, orig, temp, dest);
        result += DIRECT_MOVE;
        result += move (n - 1, temp, dest, orig) ;
	return result;
      } // method move

} // class MoveMain