Hanoi Tower Problem

The Hanoi tower problem [also known as Hanoi] is an ancient legend in India.

It is rumored that the epoch-making God Blama left three diamond rods in a temple, the first is covered with 64 round gold pieces, the largest one at the bottom, the other one smaller than a small, sequentially stacked up, the temple of the monks tirelessly to move them from this stick to another stick, the provisions can be used in the middle of a stick as a help, But only one can be moved at a time, and the big cannot be placed on the small. It is this seemingly simple problem, but it has troubled people for more than thousand years.

Later, the legend evolved into a Hanoi game, play as follows:

1. There are three Poles a,b,c. There are several plates on the A-pole.
2. Each time you move a plate, the small one can only be stacked on top of the big one.
3. Move all the plates from the A to the C-bar

Problem-solving thinking: Only three towers were given, and we used C tower to pile the discs in Tower B. First, the tower 1th is placed in the B tower, a tower 2nd disk in the C tower, and then placed in the B Tower of the 1th disk in C tower, the C tower has two discs as required from the bottom up from small to large arrangement. Next will be a tower of the 3rd disk in B Tower, the C Tower of the 1th disk in the B tower, the C-Tower 2nd disc in a tower, and then the B-tower 1th disk in a tower, when the C tower empty, 1th No. 2nd is ordered in a tower, b tower only 3rd disc. At this time, the B tower 3rd disk in C Tower, put a tower 1th in Tower B, a tower 2nd room in C Tower, and then the B tower 1th in C Tower, at this time b tower empty, C tower according to the requirements of the 123th disk. This time, the tower 4th is placed in Tower B, this time it will be more troublesome to put the C tower number 1th in Tower A. Tower 2nd in Tower B, and then put a tower 1th in Tower B, C Tower 3rd in a tower, and then put the B tower 1th in Tower C, the B tower 2nd in a tower, and then C-Tower 1th in a tower, when C tower is empty, B Tower only 4th disc, a tower according to the requirements of the room has 123 to n disc, missing 4th disc. Now put the B tower 4th disc room in Tower C, now push back, put a tower 1th room in C Tower, Tower 2nd in Tower B, and then put the C tower 1th in Tower B, a tower 3rd room C Tower, this time is just 3rd pressure 4th in C Tower, and then, b Tower 1th in a tower, the C Tower of 2nd placed in Tower C, Put the tower 1th in Tower C, this is just pushed back, at this time b tower empty, a tower is the top of the 5th disc, C tower according to the requirements of the 1234th disk.

According to this recursive method, the n-1 disk is placed on the C tower, the nth disc is placed in Tower B, and a tower is now empty. The n disk is the largest disc, according to the question we finally put the largest disk in the B tower, the use of an empty a tower combined with the BC Tower pushed back, you can put n disks as required in the B tower.

1 Import Java.io.BufferedReader; 2 Import Java.io.InputStreamReader; 3  4 public class Hanoi {5 public     static void Main (String args[]) throws Exception {6         int n; 7         Bufferedre Ader buf =  8                 new BufferedReader (New InputStreamReader (system.in)); 9         System.out.print ("Please enter the number of disks:");         n = integer.parseint (Buf.readline ());         Hanoi Hanoi = new Hanoi ();         hanoi.move (n, ' A ', ' B ', ' C ');     }14 15 Public     void Move (int n, char A, char B, char c) {         if (n = = 1)             System.out.println ("disk" + N + "by" + A + "Move to" + C), or         else {move             (n-1, A, C, b),             System.out.println ("disk" + N + "from" + A + "to" + C); 21< C17/>move (n-1, B, A, c);         }23     }24}

Hanoi Tower Problem