Question

I have 3 classes coded in c++. They are all simple, but compiler gives alot error. Each class in a cpp file and header file. What can be the possible problems?
One of it is “base class undefined”.

class re {
  int i;
  int j;
  string a;
  re(int,int,int);
  ~re();
}

class Pre:public re {
  int k;
  public:
    Pre(int,int,int);
   ~Pre();
}

class MPre:public Pre {
  int z;
  public:
      MPre(int);
     ~Mpre(int);
}

Answer 1

Possible mistakes :

• re class constructor is not public. Are you aware of this?

• MPre constructor gets one input, so you have to write default constructor for Pre class.

• Be careful when adding header files. For example, Pre class needs re class’ header file.

• Also, you don’t need to write destructor unless you add pointer variables to classes