题解 | #跳台阶#

class Solution:
    def jumpFloor(self, number):
        if number==0:
            return 0
        elif number==1:
            return 1
        elif number==2:
            return 2
        else:
            a,b=1,2
            while number>2:
                a,b=b,a+b
                number-=1
            return b