#include <iostream>
using namespace std;
 
class TestClass{
protected:
    int num;
public:
    TestClass(int n):num(n){
        cout<<this<<" : init of : " <<this->num<<endl;
    }
    TestClass(const TestClass& t):num(t.num){
        cout<<this<<" : copyInit of : " <<this->num<<endl;
    }
    virtual void printNum () const { cout << "NUM: " << num << endl; }
};
 
class TestClassDerived : public TestClass {
public:
    TestClassDerived(int n):TestClass(n){}
    virtual void printNum () const { cout << "DERIVED NUM: " << num << endl; }
};
 
 
int main(int argc, const char * argv[]){
    const TestClass t1 = TestClass(100); //option1
    TestClassDerived td2(100);
    const TestClass &t2 = TestClassDerived(100); //option2
    t1.printNum();
    t2.printNum();
}

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