f(n-1)=f(n-2)+f(n-3)+…f(1)
f(n)=f(n-1)+f(n-2)+…f(1)=2(f(n-2)+f(n-3)+…f(1))=2*f(n-1)
# -*- coding:utf-8 -*-
class Solution:
def jumpFloorII(self, number):
# write code here
if number <= 0:
return 0
else:
return pow(2,number-1)
