汉诺塔递归函数hanoi

def hanoi(n,src,dst,mid):
    global count
    if n==1:
        print('{}:{}->{}'.format(1,src,dst))
        count+=1
    else:
        hanoi(n-1,src,mid,dst)
        print('{}:{}->{}'.format(n,src,dst))
        count+=1
        hanoi(n-1,mid,dst,src)
count=0
hanoi(3,'A','C','B')
print(count)