递归

1：递归输出三角形

import sys

def star(count):
    if count==9:
        sys.exit()
    else:
        print("*" * count)
        count+=1
        star(count)
star(1)

*
**
***
****
*****
******
*******
********

 

 

2：递归计算1-100的和

def count_number(number):
    if number==1:
        return 1
    number+=count_number(number-1)
    return number
print(count_number(100))

or

def num_c(number):
    if number==1:
        return 1
    return number+num_c(number-1)
print(num_c(100))

3:递归计算N的阶乘

def num_c(number):
    if number==1:
        return 1
    return number*num_c(number-1)
print(num_c(11))


4:计算x的n次方

def num_n(x,n):
    if n==1:
        return x
    return x*num_n(x,n-1)
print(num_n(9,9))