在逆境中求生存的全，有志难伸的行，及善良婉柔的仪和乐观的珊，他们在逆境中求生存，感觉就像是你我故事的浓缩，故事尾声，行又恢复了工程师的本业，全也在报业上找到了目标，正当一切都值得庆祝之际，婉仪的哥哥和弟弟竟然为了赚钱不断使用卑劣手段，在工地偷工减料。
A program based on policy mode consists of at least two parts. The first part is a set of policy classes, which encapsulate specific algorithms and are responsible for specific calculation processes. The second part is the environment class Context, which receives the client's request and then delegates the request to a policy class. We first use traditional object-oriented to implement it.
