Thread: Inheritance

Code:

//---------------------------------------------------------------------------
#include <vcl.h>
#include<iostream>
#include<fstream>
#include<stdlib.h>
#include<conio.h>
using namespace std;
#pragma hdrstop
//---------------------------------------------------------------------------
class Base{
public:
void Get_Array();
int max();
void print();
Base();
~Base();
Base(Base&);
int& getsize();
int*& getpointer();
private:
int *p, size;
};
//----------------------------------------------------------------------------
class Derived:public Base{
public:
Derived();
~Derived();
Derived(Derived& other);
void swap(Derived& other1, Derived& other2);
void swapsize(Derived& other2);
void Add(Derived& other1,Derived& other2);
Derived& operator+=(Derived& other);
};
//---------------------------------------------------------------------------
#pragma argsused
int main(int argc, char* argv[])
{       Derived A,B;
        A.Get_Array();  B.Get_Array();
        if(A.size==B.size){
                if(A.max()>B.max())
                swap(A,B);
                else A+=B;
                A.print(); }
                else{   Derived C(A);
                        C.size=A.size+B.size;
                        C.Add(A,B);
                        C.print(); }
        getch();
        return 0;
}
//---------------------------------------------------------------------------
void Base::Get_Array(){
cout<<"How many numbers are you going to enter: ";
   cin>>size;
   p=new int[size];
   cout<<"Enter your numbers: ";
   for(int i=0;i<size;i++)
   cin>>p[i];
   cout<<endl;}
//---------------------------------------------------------------------------
int Base::max(){
int temp=p[0];
for(int i=0;i<size-1;i++)
if(p[i]>temp)
temp=p[i];
return temp;}
//---------------------------------------------------------------------------
void Base::print(){
for(int i=0;i<size;i++)
cout<<p[i]<<" ";
cout<<endl; }
//---------------------------------------------------------------------------
Base::Base(){
size=0;
p=NULL;}
//---------------------------------------------------------------------------
Base::~Base(){
delete [] p;}
//---------------------------------------------------------------------------
Base::Base(Base& other){
        size=other.size;
        p=new int[size];
        for(int i=0;i<size;i++)
        p[i]=other.p[i];}
//---------------------------------------------------------------------------
int& Base::getsize(){
return size;}
//---------------------------------------------------------------------------
int*& Base::getpointer(){
return p;}
//---------------------------------------------------------------------------
Derived::Derived(){
getsize()=0;
getpointer()=NULL;}
//---------------------------------------------------------------------------
Derived::~Derived(){
}
//---------------------------------------------------------------------------
Derived::Derived(Derived& other){
        getsize()=other.getsize();
        getpointer()=new int[getsize()];
        for(int i=0;i<getsize();i++)
        getpointer()[i]=other.getpointer()[i];}
//---------------------------------------------------------------------------
void Derived::swap(Derived& other1, Derived& other2){
int *&q=other1.getpointer();
int *&k=other2.getpointer();
int * temp;
temp=q;
q=k;
k=temp;
other1.swapsize(other2);}
//---------------------------------------------------------------------------
void Derived::swapsize(Derived& other2){
int temp;
temp=other2.getsize();
other2.getsize()=getsize();
getsize()=temp;}
//---------------------------------------------------------------------------
void Derived::Add(Derived& other1,Derived& other2){
int *temp;
temp=new int[getsize()+other1.getsize()];
for(int i=0;i<other1.getsize();i++)
temp[i]=getpointer()[i];
for(int i=other1.getsize();i<2*other1.getsize();i++)
temp[i]=other1.getpointer()[i-other1.getsize()];
for(int i=2*other1.getsize();i<getsize()+other1.getsize();i++)
temp[i]=other2.getpointer()[i-2*other1.getsize()];
delete [] getpointer();
getpointer()=temp;
getsize()+=other1.getsize();}
//---------------------------------------------------------------------------
Derived& Derived::operator+=(Derived& other){
int *&q=getpointer();
int *&k=other.getpointer();
for(int i=0;i<getsize();i++)
q[i]+=k[i];
return *this;}
//---------------------------------------------------------------------------

How can we access "A.size" or "B.size" or "C.size"?

Either you make the relevant functions friend of the classes:
C++ Friend Functions
or you make size public. This is however in my opinion bad design and the correct way to do things is through getters and setters.

Data members of the classes have to be private. I'm trying to learn about friend functions.

Some history

Originally Posted by rags_to_riches

Some history

LoL History repeats itself. Maybe that's a dejavu for you, only for you...