Is there any implimentation of Frame Stewart algorithm in C language. I have the following code in python which works fine.
def FrameStewart(ndisks,npegs):
if ndisks ==0: #zero disks require zero moves
return 0
if ndisks == 1 and npegs > 1: #if there is only 1 disk it will only take one move
return 1
if npegs == 3:#3 pegs is well defined optimal solution of 2^n-1
return 2**ndisks - 1
if npegs >= 3 and ndisks > 0:
potential_solutions = (2*FrameStewart(kdisks,npegs) + FrameStewart(ndisks-kdisks,npegs-1) for kdisks in range(1,ndisks))
return min(potential_solutions) #the best solution
#all other cases where there is no solution (namely one peg, or 2 pegs and more than 1 disk)
return float("inf")
a = int(raw_input("Disks [>] "))
b = int(raw_input("rods [>] "))
print FrameStewart(a, b) #prints 161
I wrote the following C code but it's not giving correct output
#include<stdio.h>
int power(int a, int b){
int p=1,i;
for(i=0;i<b;i++){
p*=a;
}
return p;
}
int min(int abc[],int n){
int min = abc[0],i;
for(i=1;i<n;i++)
{
if(abc[i]<min){
min = abc[i];
}
}
return min;
}
int hanoi(int rods, int disks)
{
int moves=2147483647,i;
if(disks==0)
return 0;
if(disks==1)
return 1;
if(rods==3)
return power(2,disks)-1;
if(rods>=3 && disks>0){
int potential_moves[disks-1];
for(i=1;i<disks;i++){
potential_moves[i-1]=2*hanoi(i,rods) + hanoi(disks-i,rods-1);
}
return min(potential_moves, disks-1);
}
return moves;
}
int main(){
int rods,disks;
printf("***** Tower of Hanoi (for n rods) *****\n");
printf("Enter no. of disks : ");
scanf("%d",&disks);
printf("Enter no. of rods : ");
scanf("%d",&rods);
if(disks>1 && rods<3){
printf("Invalid input rods must be greater than 2 for 2 or more disks\n");
return -1;
}
int moves = hanoi(rods, disks);
printf("Minimum np. of moves are : %d\n", moves);
return 0;
}
Can anyone tell me why is my code incorrect or a correct implimentation of Frame Stewart algorithm in C.
Your logic is correct but it have a simple yet hard-to-find mistake. You have reversed the arguments when calling the function recursively. take a look here
potential_moves[i-1]=2*hanoi(i,rods) + hanoi(disks-i,rods-1);
the line should be
potential_moves[i-1]=2*hanoi(rods,i) + hanoi(rods-1, disks-i);
and problem solved!.