C++ Programming Code Examples

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Program To Implement Tower Of Hanoi Alogithm Using Recursion.

Program To Implement Tower Of Hanoi Alogithm Using Recursion.
This program shows the movements of disk from one tower to another when a key is pressed.

Code :


#include<iostream.h>
#include<stdio.h>
#include<conio.h>

class tower
{
	int *t1,*t2,*t3;
	int x,y,z;
	public:
	void disp_tower();
	void move_disk(int tx,int ty);
	void toh(int n,int a,int b,int c);
	tower(int no);
	~tower();
};

tower :: tower(int no)
{
	t1 = new int[no+1];
	t2 = new int[no+1];
	t3 = new int[no+1];
	x  = no;
	y  = z = 0;

	for(int i=0,j=no ; i<no ; i++,j--)
	{
		t1[i] = j;
		t2[i] = t2[i] = 0;
	}
	t1[no] = t2[no] = t3[no] = 0;
}

tower :: ~tower()
{
	delete []t1;
	delete []t2;
	delete []t3;
}
void tower :: disp_tower()
{
	clrscr();
	cout<<"

 X :: ";
	for(int i=0;i<x;i++)
	{
		cout<<" "<<t1[i];
	}
	cout<<"

 Y :: ";
	for(i=0;i<y;i++)
	{
		cout<<" "<<t2[i];
	}
	cout<<"

 Z :: ";
	for(i=0;i<z;i++)
	{
		cout<<" "<<t3[i];
	}
	getch();
}

void tower :: toh(int n,int tx,int ty,int tz)       //x to y using z
{

	if(n>=1)
	{
		toh(n-1,tx,tz,ty);
		move_disk(tx,ty);         	//x to y
		disp_tower();
		toh(n-1,tz,ty,tx);
	}
}

void tower :: move_disk(int tx,int ty)
{
	switch(tx)
	{
		case 1:
			{
				if(ty==2)
					t2[y++] = t1[--x];
				else
					t3[z++] = t1[--x];
			}break;
		case 2:
			{
				if(ty==1)
					t1[x++] = t2[--y];
				else
					t3[z++] = t2[--y];
			}break;
		case 3:
			{
				if(ty==1)
					t1[x++] = t3[--z];
				else
					t2[y++] = t3[--z];
			}break;
	}//end of switch
}
//------------------------------------------------------------------------
---
int main(void)
{
	clrscr();
	cout<<"Enter the no. of disks::";
	int no;
	cin>>no;
	tower obj(no);
	obj.disp_tower();
	obj.toh(no,1,2,3);
	getch();
	return 0;
}
//------------------------------------------------------------------------
---