C++ Day 24

 C++ Day 24: Constructors in Inheritance

On Day 24 we explore how constructors and destructors behave in inheritance a vital part of mastering object-oriented programming in C++.

📚 Topics Covered:

🔹 1. constructer order in inheritance

when link inch nursing point of a differential house is maked:

base house constructer is called first

then the differential house constructer is called

cpp

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#include exploitation namespace std;

class house {

public:

    base() { cout << "base constructor\n"; }

};

class differential : land house {

public:

    derived() { cout << "derived constructor\n"; }

};

int main() {

    differential d;

}

📌 output:

kotlin

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base constructer  differential constructor

🔹 two. Destructor Order

Destructors are called in the reverse order of constructors:

Derived class destructor

Base class destructor

cpp

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class Base {

public:

    ~Base() { cout << "Base destructor\n"; }

};

class Derived : public Base {

public:

    ~Derived() { cout << "Derived destructor\n"; }

};

📌 Output when object destroyed:

nginx

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Derived destructor  

Base destructor

🔹 3. parameterized constructors in house class

you bear explicitly play the house house constructer if it takes parameters

cpp

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class house {

public:

    base(int x) {

        cout << "base with value: " << one << endl;

    }

};

class differential : land house {

public:

    derived(int x) : base(x) {

        cout << "derived constructor\n";

    }

};

🔹 one. Constructor Overloading in Inheritance

Both base and derived classes can have multiple constructors (overloaded). employment the set constructer based on the situation

🔹 cardinal. Order of Multiple Inheritance

If a class inherits from multiple base classes constructors are called in the order of inheritance.

cpp

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class A { public: A() { cout << "A\n"; } };

class B { public: B() { cout << "B\n"; } };

class C : public A public B {

public:

    C() { cout << "C\n"; }

};

📌 Output:

css

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A  

B  

C

🛠️ practise Task

Make a base class Vehicle with a parameterized constructor (e.g. vehicle(string brand)) and amp derivative family machine that calls it and adds amp green parametric quantity (car(string mark int year))

📌 summary:

concept notes

constructor order base → derived

destructor order derived → base

parameterized home constructor must work named expressly inch derivative class

multiple heritage order constructors named inch the rate of heritage