#include <iostream>
#include <fstream>
using namespace std;
class BaseClass {
public:
    BaseClass() {}
    
    virtual void print() {
        cout << "base class" << endl;
    }
    
};
class DerivedClass : public BaseClass {
public:
    DerivedClass(){}
    void print()
    { cout << "derived class" << endl;
    }
};
int main(){
    BaseClass *b = new DerivedClass();
    
    b->print();
    
    return 0;
}