Towers Of Hanoi Recursive

TowersOfHanoiRecursive.java

/**The Tower of Hanoi or Towers of Hanoi is a mathematical game or puzzle. 
 * It consists of three rods, and a number of disks of different sizes which can slide onto any rod.
 * The puzzle starts with the disks neatly stacked in order of size on one rod, the smallest at the top,
 * thus making a conical section.
 * The objective of the puzzle is to move the entire stack to another rod, obeying the following rules:
 * Only one disk may be moved at a time.
 * Each move consists of taking the upper disk from one of the rods and sliding it onto another rod,
 * on top of the other disks that may already be present on that rod.
 * No disk may be placed on top of a smaller disk.**/
import java.io.*;
public class TowersOfHanoiRecursive
{
    static int flag;
    public static void main()throws IOException
    {
        TowersOfHanoiRecursive obj=new TowersOfHanoiRecursive();
        BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
        System.out.println("Enter number of rings");
        int N=Integer.parseInt(br.readLine());
        flag=0;
        obj.recmove('A','B','C',N);
        System.out.println("No. of Moves ---> "+flag);//Moves((2^N)-1)
        flag=0;
        obj.Towers(N,'A','B','C');
        System.out.println("No. of Moves ---> "+flag);//Moves((2^N)-1)
    }

    /**
     * Recursively Move n-1 disks to get largest n then move back n-1 disks in place to get disks in order.
     * Recursive function terminates when stack of small disks is reduced to 1 disk.. i.e n=1. 
     */
    /** Moves N Discs from A to C */
    void recmove(char a,char b,char c,int n)
    {
        if(n==0)
            System.out.println("WRONG INPUT !!!");
        if(n==1)
        {
            System.out.println("Move from "+a+" to "+c);
            flag++;
        }
        if(n>1)
        {
            recmove(a,c,b,n-1);
            recmove(a,b,c,1);
            recmove(b,a,c,n-1);
        }
    }
    /** Moves N Discs from A to B */
    public static void Towers(int numDisks,char src, char dest, char temp)
    {
        if (numDisks == 1)
        {
            flag++;
            System.out.println("Move top disk from pole "+src+" to pole "+dest);
        }
        else
        {
            Towers(numDisks-1,src,temp,dest);
            Towers(1,src,dest,temp);
            Towers(numDisks-1,temp,dest,src);
        }
    }
}