/* Write C programs that use both recursive and non-recursive functions
To solve Towers of Hanoi problem.*/
#include<conio.h>
#include<stdio.h>
/* Non-Recursive Function*/
void hanoiNonRecursion(int num,char sndl,char indl,char dndl)
{
char stkn[50],stksndl[50],stkindl[50],stkdndl[50],stkadd[50],temp;
int top,add;
top=NULL;
one:
if(num==1)
{
printf("\nMove top disk from needle %c to needle %c ",sndl,dndl);
goto four;
}
two:
top=top+1;
stkn[top]=num;
stksndl[top]=sndl;
stkindl[top]=indl;
stkdndl[top]=dndl;
stkadd[top]=3;
num=num-1;
sndl=sndl;
temp=indl;
indl=dndl;
dndl=temp;
goto one;
three:
printf("\nMove top disk from needle %c to needle %c ",sndl,dndl);
top=top+1;
stkn[top]=num;
stksndl[top]=sndl;
stkindl[top]=indl;
stkdndl[top]=dndl;
stkadd[top]=5;
num=num-1;
temp=sndl;
sndl=indl;
indl=temp;
dndl=dndl;
goto one;
four:
if(top==NULL)
return;
num=stkn[top];
sndl=stksndl[top];
indl=stkindl[top];
dndl=stkdndl[top];
add=stkadd[top];
top=top-1;
if(add==3)
goto three;
else if(add==5)
goto four;
}
/* Recursive Function*/
void hanoiRecursion( int num,char ndl1, char ndl2, char ndl3)
{
if ( num == 1 ) {
printf( "\nMove top disk from needle %c to needle %c.", ndl1, ndl2 );
return;
}
hanoiRecursion( num - 1,ndl1, ndl3, ndl2 );
printf( "\nMove top disk from needle %c to needle %c.", ndl1, ndl2 );
hanoiRecursion( num - 1,ndl3, ndl2, ndl1 );
}
int main()
{
int no;
//clrscr();
printf("Enter the no. of disks to be transferred: ");
scanf("%d",&no);
if(no<1)
printf("\nThere's nothing to move.");
else
printf("Non-Recursive");
hanoiNonRecursion(no,'A','B','C');
printf("\nRecursive");
hanoiRecursion(no,'A','B','C');
return 0;
}
OUTPUT:
Enter the no. of disks to be transferred: 3 Non-Recursive Move top disk from needle A to needle C Move top disk from needle A to needle B Move top disk from needle C to needle B Move top disk from needle A to needle C Move top disk from needle B to needle A Move top disk from needle B to needle C Move top disk from needle A to needle C Recursive Move top disk from needle A to needle B. Move top disk from needle A to needle C. Move top disk from needle B to needle C. Move top disk from needle A to needle B. Move top disk from needle C to needle A. Move top disk from needle C to needle B. Move top disk from needle A to needle B.
Reference:C Programming and Data Structures by E.Balagurusamy. TMH Publishers.