Given a positive number, find out all the prime numbers under it.

Sample Input:

27

Sample Output:

There are 9 prime numbers under 27:
2, 3, 5, 7, 11, 13, 17, 19, 23

数据结构和算法：初级练习题#1 – 找质数

给定一个正整数，找出所有小于它的质数。

输入样例：

27

输出样例：

小于27的质数有9个：2, 3, 5, 7, 11, 13, 17, 19, 23

Python Solution