What are the advantages and disadvantages of polymorphism in C++?

Advantages and Disadvantages of Polymorphism in C++: Advantages: Code Reusability: Common code can handle different object types. Extensibility: Easily add new classes without modifying existing code. Flexibility and maintainability: separation of behavior and type improves code flexibility. Disadvantages: Runtime overhead: Virtual function dispatch leads to increased overhead. Code Complexity: Multiple inheritance hierarchies add complexity. Binary size: Virtual function usage increases binary file size. Practical case: In the animal class hierarchy, polymorphism enables different animal objects to make sounds through the Animal pointer.

Advantages and Disadvantages of Polymorphism in C++

Polymorphism is an important feature in object-oriented programming. It allows objects to respond to the same function call in different ways. In C++, polymorphism is primarily achieved through virtual functions.

Advantages:

• ##Code reusability: Polymorphism allows base class pointers to point to objects of derived classes, so generic code to handle different object types.
• Extensibility: New classes can be easily added without modifying existing code. Just implement virtual functions for the new class.
• Flexibility and maintainability:With polymorphism, the behavior of objects can be separated from their types, which makes the code more flexible and easier to maintain.

Disadvantages:

• Runtime overhead: Since virtual function dispatch is performed at runtime, it may be more expensive than Non-polymorphic function calls incur higher overhead.
• Code Complexity: Polymorphism can make code more complex, especially when multiple inheritance hierarchies are involved.
• Binary size: Using virtual functions will increase the size of the binary file because of the need to record the dynamic type of the object.

Practical case:

Consider the following animal class hierarchy:

class Animal {
public:
  virtual void speak() const = 0;
};

class Dog : public Animal {
public:
  virtual void speak() const override { std::cout << "Woof!" << std::endl; }
};

class Cat : public Animal {
public:
  virtual void speak() const override { std::cout << "Meow!" << std::endl; }
};

Using polymorphism, we can write the following code, so All animals make sounds:

std::vector<Animal*> animals;
animals.push_back(new Dog());
animals.push_back(new Cat());

for (auto animal : animals) {
  animal->speak();
}

Output:

Woof!
Meow!

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