1018递归解法（Python）

注意事项:只关注上、下两数的关系即可

参考代码:

N = int(input())

output = 0

times = 0

def count_sum(up_data, down_data) :

    global times, output

    times += 1

    temp = up_data

    output += up_data / down_data

    up_data = up_data + down_data

    down_data = temp

    if times < N :

        count_sum(up_data, down_data)

    else :

        print(round(output, 2))

count_sum(2, 1)