Protected Keyword in C++

#include<iostream.h>
#include<conio.h>
class Base
{
protected:
int a,b;
};
class Derived:private Base
{
public:
void GetPut()
{
cout<<"\n Enter A Value :";
cin>>a;
cout<<"\n Enter B Value :";
cin>>b;
cout<<"\n A =  "<<a;
cout<<"\n B =  "<<b;
}
};
class Derived1:public Derived /* Derived.a & Derived.b is not accessible */
{
};
void main()
{
Derived d;
d.GetPut();
}

==================
#include<iostream.h>
#include<conio.h>
class Base
{
protected:
int a,b;
};
class Derived:public Base
{
public:
void GetPut()
{
cout<<"\n Enter A Value :";
cin>>a;
cout<<"\n Enter B Value :";
cin>>b;
cout<<"\n A =  "<<a;
cout<<"\n B =  "<<b;
}
};
void main()
{
Derived d;
d.GetPut();
}

=====================

#include<iostream.h>

#include<conio.h>

class Base

{

protected:

int a,b;

public:

Base()

{

a=10;

b=20;

}

void Put()

{

cout<<"\n A value is :"<<a;

cout<<"\n B value is :"<<b;

}

};

class Derived:public Base

{

private:

int c;

public:

Derived()

{

c=100;

}

void Put()

{

cout<<"\n C =  "<<c;

}

};

void main()

{

Derived d;

clrscr();

d.Put();

d.Base::Put();

getch();

}