Drived_class_constructors.cpp

#include <iostream>
using namespace std;

/*
Case1:
class B: public A{
    // Order of execution of constructor -> first A() then B()
};

Case2:
class A: public B, public C{
    // Order of execution of constructor -> B() then C() and A()
};

Case3:
class A: public B , virtual public C{
    // Order of execution of constructor -> C() then B() and A()
};

*/

class Base1
{
    int data1;

public:
    Base1(int i)
    {
        data1 = i;
        cout << "Base1 class constructor called" << endl;
    }
    void printData1(void)
    {
        cout << "The value of data1 is " << data1 << endl;
    }
};
class Base2
{
    int data2;

public:
    Base2(int i)
    {
        data2 = i;
        cout << "Base2 class constructor called" << endl;
    }
    void printData2(void)
    {
        cout << "The value of data2 is " << data2 << endl;
    }
};

class Derived : public Base1, public Base2  // for change the exicution order of the consturctor you have to change in this line
{
    int derived1, derived2;

public:
    Derived(int a, int b, int c, int d) : Base1(a), Base2(b)
    {
        derived1 = c;
        derived2 = d;
    }
    void printDerived(void)
    {
        cout << "The value of derived1 is " << derived1 << endl;
        cout << "The value of derived2 is " << derived2 << endl;
    }
};

int main()
{
    Derived O1(1, 2, 3, 4);
    O1.printData1();
    O1.printData2();
    O1.printDerived();
    return 0;
}