汉诺塔

 1 count = 0
 2 def hanoi(n, src, dst, mid):
 3     global count
 4     if n == 1:
 5         print("{}:{}->{}".format(1,src,dst))
 6         count += 1
 7     else :
 8         hanoi(n-1, src, mid, dst)
 9         print("{}:{}->{}".format(n,src,dst))
10         count += 1
11         hanoi(n-1, mid, dst, src)
12 hanoi(eval(input()),"A","C","B")
13 print(count)