题目描述
一只青蛙一次可以跳上1级台阶,也可以跳上2级……它也可以跳上n级。求该青蛙跳上一个n级的台阶总共有多少种跳法。
c++实现
class Solution {
public:
int jumpFloorII(int number) {
if(number<=0)
return 0;
if(number==1)
return 1;
return 2*jumpFloorII(number-1);
}
};
Java实现
public class Solution {
public int JumpFloorII(int target) {
if(target<=0)
return 0;
if(target==1)
return 1;
return 2*JumpFloorII(target-1);
}
}
python实现
# -*- coding:utf-8 -*-
class Solution:
def jumpFloorII(self, number):
return pow(2, number-1)
# write code here