Virtual functions are hierarchical. : Virtual « Function « C++

Virtual functions are hierarchical.

#include <iostream>
using namespace std;

class BaseClass {
  int i;
  BaseClass(int x) { 
     i = x; 
  virtual void myFunction()
    cout << "Using BaseClass version of myFunction(): ";
    cout << i << '\n';

class DerivedClass1 : public BaseClass {
  DerivedClass1(int x) : BaseClass(x) {}
  void myFunction() 
    cout << "Using DerivedClass1's version of myFunction(): ";
    cout << i*i << '\n';

class DerivedClass2 : public BaseClass {
  DerivedClass2(int x) : BaseClass(x) {}

int main()
  BaseClass *p;
  BaseClass ob(10);  
  DerivedClass1 derivedObject1(10);   
  DerivedClass2 derivedObject2(10); 
  p = &ob;
  p->myFunction();                       // use BaseClass's myFunction()

  p = &derivedObject1;
  p->myFunction();                       // use DerivedClass1's myFunction()
  p = &derivedObject2;
  p->myFunction();                       // use BaseClass's myFunction()

  return 0;


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