20_oops.cpp

#include<iostream>
using namespace std;
class Base {
 int data1; //private by default and is not inheritable
 public:
 int data2;
 void setdata();
 int getdata1();
 int getdata2();
};

void Base:: setdata(void){
    data1=10;
    data2=20;
}

int Base:: getdata1(){
    return data1;
}

int Base::getdata2(){
  return data2;
}

class Derived: private Base{ //class is being derived publically.
    
int data3;
 public:
  void process();
  void display();
};

void Derived::process(){
    setdata();
    data3 = data2*getdata1();
}
void Derived::display(){
    cout<<"value of data 1 is"<<" "<<getdata1()<<endl;
     cout<<"value of data 2 is"<<" "<<data2<<endl;
      cout<<"value of data 3 is"<<" "<<data3<<endl;

}
int main (){
    Derived der;
   // der.setdata();
    der.process();
    der.display();
return 0;
}