这是第3章的答案，这些都是我珍贵的代码，我学习c++的时候，一章一章的编出来的，不仅有课后题的答案，还有文档说明，非常详细，希望能帮到你们!-This is the answer in Chapter 3, these are my precious code, I learning c++ when a chapter made up, not only the answer to the after-school title, as well as the document describes, in great detail, hoping to help to you!