The problem is known as NP hard no matter whether group sub lotting is admissible or not.

无论是对于成组加工情形还是分组情形，该问题都可以被证明是NP困难的。

Can treat difficult objectively, virtuous tolerant improve oneself, not content with one's lotting, principle that I conduct oneself.

能客观地对待困难，贤惠、宽容、自强、知足、是我做人的原则。

This paper introduces several methods to generate random Numbers and their advantages and shortcomings, and at last realizes the application of random Numbers in the field of "online lotting system".

本文介绍了几种常见随机数的产生方法以及其优缺点，最后实现了“在线抽签系统”中的应用。