关于hw3

[Charlielcy]

TA师兄好~

（1）在子类FileInterfaceImpl的实现中写了这个构造函数：

FileInterfaceImpl::FileInterfaceImpl(const string& filename) {...}

但VS会报错：error C2259: “FileInterfaceImpl”: 不能实例化抽象类。 可是这个是子类啊...为什么不能实例化？

（2）请问SaveTo这个函数返回bool值的作用是什么？

（3）请问每次作业的“风格”一栏的评判标准有哪些？要注意哪些问题？

谢谢！

[zhchbin]

1. Because you didn't override some of the member function of base class.
2. Please read: http://www.cplusplus.com/reference/fstream/ifstream/open/. Sometimes that file open operation will fail.
3. We use cpplint.py to check your code. Recommend your code style should follow Google C++ code style. By the way we have declared this on class.