/* Write C programs that use both recursive and non-recursive functions
To solve Towers of Hanoi problem.*/

include

include

/* 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.