题目说 print the C*2 prime numbers from the center of the list if there are an even number of prime numbers or (C*2)-1 prime numbers from the center of the list if there are an odd number of prime numbers in the list. 
样例第一个21 2
1-21有8个质数，不是应该打印C*2 = 4个吗？为什么只打印了3个！！！

• 我晕~~~ 1也算质数？？？！！！！ (274) K208 2005-10-02 19:22:15