Tower-of-Hanoy-Visual-Simulation.py

class tower:
    def __init__(self, position, n):
        #initial position as 0,1, or 2
        self.position=position
        # sanity check
        if position > 2:
            raise ValueError('tower position not valid. must be between 0 and 2')
        if n < 1:
            raise ValueError('disk number not valid. must be between 0 and 2')
        #initialize an empty stack to hold the disks
        self.disks=[]
        #if original tower, fill up with disks
        if position==0:    
            for x in range(n,0,-1):
                self.disks.append(x)

    def addDisk(self,x):
        #check if x is smaller than top disks
        if len(self.disks) !=0 and x > self.disks[-1]:
            raise ValueError('new disk bigger than the top')
        self.disks.append(x)
    
    def removeDisk(self):
        return self.disks.pop(-1)

def printStars(x):
    for i in range(0,x):
        print('*',end='')

def shiftDisk(original, destination, intermediate, n):
    if n==1:
        transferDisk=original.removeDisk()
        destination.addDisk(transferDisk)
        #print state after each transfer
        drawTowers(original,destination,intermediate)
    else:
        shiftDisk(original, intermediate,destination, n-1)
        shiftDisk(original,destination,intermediate,1)
        shiftDisk(intermediate,destination,original,n-1)
    

def drawTowers(a,b,c):
    #figure out the original positions of the tower
    temp=[a,b,c]
    for t in temp:
        if t.position==0:
            original=t
        elif t.position==1:
            destination=t
        elif t.position==2:
            intermediate=t

    maxLen=max(len(original.disks),len(destination.disks),len(intermediate.disks))
    for i in range(0,maxLen,1):
        if i < len(original.disks):
            printStars(original.disks[i])
        print('\t',end='')
        if i < len(destination.disks):
            printStars(destination.disks[i])
        print('\t',end='')
        if i < len(intermediate.disks):
            printStars(intermediate.disks[i])
        print('\n')
    print('--------------------------')
        
            


if __name__ == "__main__":
    print("enter the number of disks: ")
    n=int(input())
    original=tower(0,n)
    destination=tower(1,n)
    intermediate=tower(2,n)
    drawTowers(original,destination,intermediate)
    shiftDisk(original,destination,intermediate,n)