Hierarchical inheritance

📘 What is Hierarchical Inheritance?

Hierarchical Inheritance occurs when multiple derived classes inherit from a single base class.

🧠 Real-Life Analogy:

Imagine a Teacher class that defines common characteristics. Then, two specialized classes like MathTeacher and ScienceTeacher inherit from it.

---

🧱 Structure:

         Base
         /    \
   Derived1  Derived2

So, each derived class gets access to the common properties of the base class, but can also define its own.

---

🔧 Syntax:

class Base {
    // Common functionality
};

class Derived1 : public Base {
    // Inherits from Base
};

class Derived2 : public Base {
    // Inherits from Base
};

---

🧪 C++ Example Program: Hierarchical Inheritance

#include <iostream>
using namespace std;

// Base Class
class Teacher {
public:
    void displaySubject() {
        cout << "Teaches subjects in school." << endl;
    }
};

// Derived Class 1
class MathTeacher : public Teacher {
public:
    void teachMath() {
        cout << "Teaches Mathematics." << endl;
    }
};

// Derived Class 2
class ScienceTeacher : public Teacher {
public:
    void teachScience() {
        cout << "Teaches Science." << endl;
    }
};

int main() {
    MathTeacher m;
    ScienceTeacher s;

    cout << "--- Math Teacher ---" << endl;
    m.displaySubject();
    m.teachMath();

    cout << "\n--- Science Teacher ---" << endl;
    s.displaySubject();
    s.teachScience();

    return 0;
}

---

✅ Output:

--- Math Teacher ---
Teaches subjects in school.
Teaches Mathematics.

--- Science Teacher ---
Teaches subjects in school.
Teaches Science.

---

🎯 Key Points:

• Both MathTeacher and ScienceTeacher inherit the method displaySubject() from the base class Teacher.
• Each derived class adds its own specific functionality.
• Encourages code reusability and organization.

---

✅ Advantages of Hierarchical Inheritance:

• Shared functionality is written only once in the base class.
• Easy to extend and maintain.
• Encourages logical class structure.

---

❌ Limitations:

• Cannot share data between sibling classes directly.
• Deep hierarchies can become hard to manage.

---

📌 Summary Table:

Class	Inherits From	Methods Inherited
Teacher (Base)	—	displaySubject()
MathTeacher	Teacher	displaySubject(), teachMath()
ScienceTeacher	Teacher	displaySubject(), teachScience()