C++ Programming Code Examples
C++ > Algorithms Code Examples
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. */
#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;
}
//------------------------------------------------------------------------
---
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