The Tower of Hanoi (also called the Tower of Brahma or Lucas' Tower, and sometimes pluralised) 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 in a neat
stack in ascending order of size on one rod, the smallest at the top,
thus making a conical shape.
The objective of the puzzle is to move the entire stack to another rod, obeying the following simple rules:- Only one disk can be moved at a time.
- Each move consists of taking the upper disk from one of the stacks and placing it on top of another stack i.e. a disk can only be moved if it is the uppermost disk on a stack.
- No disk may be placed on top of a smaller disk.
We Implemented TOH using applets in java.
//CODE:
/*
* To change this license header, choose
License Headers in Project Properties.
* To change this template file, choose Tools |
Templates
* and open the template in the editor.
*/
//package netbeans;
import
java.applet.*;
import
java.awt.*;
import
java.awt.event.*;
/**
*
* @author Vijay S Y
*/
public class TOH extends Applet implements ItemListener ,ActionListener,Runnable {
boolean first;
Choice from
,to;
int[] compArr=new
int[]{0,2,0,1,2,1,0,2,1,0,1,2,0,2};
Button submit,reset,plycom;
String clr[]=new
String[]{"RED","GREEN","BLUE"};
int f,t,cf,ct;
Thread
circleThread;
int tos[]=new
int[]{2,-1,-1};
int [][]stack=new
int [][]{{2,1,0},
{3,3,3},
{3,3,3}};
boolean
isvalid(){
print();
if(ct==t&&cf==f) return true;
if(tos[t]==-1||stack[f][tos[f]]<stack[t][tos[f]]){
tos[t]++;
stack[t][tos[t]]=stack[f][tos[f]];
tos[f]--;
ct=t;
cf=f;
return true;
}
return false;
}
void print(){
for(int i=0;i<3;i++)
System.out.print(tos[i] +
"\t");
System.out.print("\n");
}
@Override
public void init() {
setLayout(new
FlowLayout(FlowLayout.CENTER));
first=false;
f=t=0;
ct=cf=5;
from =new Choice();
to= new Choice();
submit =new Button("SUBMIT");
reset=new Button("RESET");
plycom=new
Button("COMPUTER_TERN");
from.add("From_A");
to.add("To_A");
from.add("From_B");
to.add("To_B");
from.add("From_C");to.add("To_C");
add(from);
add(to);
add(submit);
add(reset);
add(plycom);
submit.addActionListener((ActionListener) this);
reset.addActionListener((ActionListener) this);
plycom.addActionListener((ActionListener) this);
from.addItemListener((ItemListener)
this);
to.addItemListener((ItemListener)
this);
}
@Override
public void itemStateChanged(ItemEvent
ie){
f = from.getSelectedIndex();
t=to.getSelectedIndex();
}
void reset(){
f=t=0;
ct=cf=5;
tos[0]=2;
tos[1]=-1;
tos[2]=-1;
//tos[3]=-1;
stack[0][0]=2; stack[1][0]=-1; stack[2][0]=-1;
stack[0][1]=1; stack[1][1]=-1; stack[2][1]=-1;
stack[0][2]=0; stack[1][2]=-1; stack[2][2]=-1;
}
@Override
@SuppressWarnings("empty-statement")
public void actionPerformed(ActionEvent
ae){
String str=ae.getActionCommand();
switch (str) {
case "SUBMIT":
repaint();
break;
case "RESET":
reset();
repaint();
break;
case "COMPUTER_TERN":
System.out.println("in
com");
comp();
break;
default:
break;
}
}
void comp(){
f=t=0;
cf=ct=5;
//*****************************************************************
tos[0]=2;
tos[1]=-1;
tos[2]=-1;
// tos[3]=-1;
stack[0][0]=2; stack[1][0]=-1; stack[2][0]=-1;
stack[0][1]=1; stack[1][1]=-1; stack[2][1]=-1;
stack[0][2]=0; stack[1][2]=-1; stack[2][2]=-1;
// stack[0][3]=0; stack[0][3]=-1; stack[0][3]=-1;
circleThread = new Thread((Runnable)
this);
circleThread.start();
}
@Override
public void run(){
for(int i=0;i<14;i+=2){
f=compArr[i];
t=compArr[i+1];
repaint();
try {
Thread.sleep(1000);
}
catch (InterruptedException evt)
{}
}
reset();
repaint();
}
@Override
public void paint(Graphics g){
//******************************************BASE
g.fillRoundRect(100, 550-100, 1020
,20,20,20);
//*******************************************C1
g.fillRoundRect(300, 190, 20,370-100,20,20);
//********************************************C2
g.fillRoundRect(600, 190,
20,370-100,20,20);
//********************************************C3
g.fillRoundRect(900, 190,
20,370-100,20,20);
//*************************************************************************************
if(!isvalid()&&first){
g.drawString("Invalid
Move",450,150);
first=true;
}
//*********************************************************************************************
for(int i=0;i<=tos[0];i++){
switch(stack[0][i]){
case 2:g.setColor(Color.GREEN);
break;
case 0:g.setColor(Color.BLUE);
break;
case 1:g.setColor(Color.RED);
break;
//
default:g.setColor(Color.yellow);
}
g.fillRoundRect(240-(50*stack[0][i]),530-100-20*i,(100*stack[0][i])+130,
20,20, 20);
}
//***************************************************************************************************
for(int i=0;i<=tos[1];i++){
switch(stack[1][i]){
case 2:g.setColor(Color.GREEN);
break;
case 0:g.setColor(Color.BLUE);
break;
case 1:g.setColor(Color.RED);
break;
//default:g.setColor(Color.yellow);
}
g.fillRoundRect(540-(50*stack[1][i]),530-100-20*i,(100*stack[1][i])+130,
20,20, 20);
}
//*********************************************************************************************
for(int i=0;i<=tos[2];i++){
switch(stack[2][i]){
case 2:g.setColor(Color.GREEN);
break;
case 0:g.setColor(Color.BLUE);
break;
case 1:g.setColor(Color.RED);
break;
//
default:g.setColor(Color.yellow);
}
g.fillRoundRect(840-(50*stack[2][i]),530-100-20*i,(100*stack[2][i])+130,
20,20,20);
}
//***************************************************************************************************
}
}
//THML FILE
