Constructors are an important concept in object-oriented programming as they are responsible for initializing objects of a class. In C++, constructors can also be categorized into two types: default constructor and parameterized constructor. These two types are like relatives to each other, with some similarities and differences.

Default Constructor

A default constructor is a special member function of a class that is automatically called when an object is created without any arguments. This constructor does not take any parameters and is often used to initialize member variables to their default values. Here’s an example of a default constructor in C++:

class MyClass {
public:
    // Default constructor
    MyClass() {
        // Initialize member variables
        // ...
    }
};

In this example, MyClass has a default constructor with no parameters. If an object of MyClass is created without any arguments, the default constructor will be called.

Parameterized Constructor

On the other hand, a parameterized constructor is a constructor that takes one or more parameters. It allows you to pass values to the constructor when creating an object, which can then be used to initialize member variables. Here’s an example of a parameterized constructor in C++:

class MyClass {
public:
    // Parameterized constructor
    MyClass(int value) {
        // Initialize member variables using the parameter value
        // ...
    }
};

In this example, MyClass has a parameterized constructor that takes an integer value as a parameter. If an object of MyClass is created with an integer argument, the parameterized constructor will be called.

Similarities and Differences

Both default and parameterized constructors are used to initialize objects, but they have some key differences:

• The default constructor is automatically called when an object is created without any arguments, while the parameterized constructor requires explicit arguments.
• The default constructor does not take any parameters, whereas the parameterized constructor takes one or more parameters.
• It is possible to have a class with both a default constructor and a parameterized constructor. In such cases, the appropriate constructor is called based on the arguments passed during object creation.

#programming #cplusplus