Explain inheritance and its types in detail.
SOLUTION....
Inheritance in C++
Definition:
Inheritance lets a derived class reuse and extend the data/behaviour of a base class, modeling an “is-a” relationship (e.g., Dog is a Animal). It improves reuse, reduces duplication, and enables polymorphism.
Basic syntax:
Access effects (visibility mode):
public inheritance: base
public→ derivedpublic, baseprotected→ derivedprotected.protected inheritance: base
public/protected→ derivedprotected.private inheritance: base
public/protected→ derivedprivate.Base
privatemembers aren’t directly accessible in derived (they still exist via the base subobject).
Ctor/Dtor order:
Base constructor runs first, then derived. Destruction is reverse: derived then base. For polymorphic bases, prefer a virtual destructor.
Overriding & polymorphism:
Mark base functions virtual, override in derived with override, and call through base pointers/references to get runtime polymorphism.
Types of Inheritance (with tiny C++ sketches)
1) Single Inheritance
One base → one derived.
2) Multilevel Inheritance
A chain of derivations.
3) Multiple Inheritance
Derived class inherits from multiple bases.
4) Hierarchical Inheritance
Multiple derived classes from the same base.
5) Hybrid Inheritance
A mix (e.g., multilevel + multiple). Often involves virtual inheritance to resolve diamonds.
#include <iostream> using namespace std; class Shape { public: virtual double area() const = 0; // polymorphic base virtual ~Shape() = default; }; class Rectangle : public Shape { double w, h; public: Rectangle(double W, double H) : w(W), h(H) {} double area() const override { return w * h; } }; class Square : public Rectangle { // multilevel (Square is a Rectangle) public: Square(double s) : Rectangle(s, s) {} }; int main() { Shape* p = new Square(5); cout << p->area() << '\n'; // 25 delete p; }