C++ Program - Default, Parameterized, and Copy Constructor

✅ C++ Program to Demonstrate Default, Parameterized, and Copy Constructor

#include <iostream>
using namespace std;

class sample {
  private:
    string name;
    int age;
  public:
    // Default constructor
    sample() {
      cout << "Enter name of the student:\n";
      cin.ignore();
      getline(cin, name);
      cout << "Enter age of the student:\n";
      cin >> age;
    }

    // Parameterized constructor
    sample(string n, int a) {  
      name = n;
      age = a;
    }

    // Copy constructor
    sample(sample &obj) {
      name = obj.name;
      age = obj.age;
    }

    void display() {
      cout << "Name: " << name << "\n";
      cout << "Age: " << age << "\n";
    }
};

int main() {
    sample s1;
    cout << "=== DEFAULT CONSTRUCTOR ===\n";
    s1.display();

    sample s2("Esther", 27);
    cout << "=== PARAMETERIZED CONSTRUCTOR ===\n";
    s2.display();

    cout << "=== COPY CONSTRUCTOR ===\n";
    sample s3(s2);
    s3.display();
}
  

📘 Explanation:

This C++ program demonstrates the use of three types of constructors in object-oriented programming:

• Default Constructor → Initializes object when no arguments are passed. Here, it asks the user to input values.
• Parameterized Constructor → Allows initialization with specific values while creating the object.
• Copy Constructor → Creates a new object by copying values from an existing object.

🧾 Sample Output:

Enter name of the student:
John
Enter age of the student:
22
=== DEFAULT CONSTRUCTOR ===
Name: John
Age: 22

=== PARAMETERIZED CONSTRUCTOR ===
Name: Esther
Age: 27

=== COPY CONSTRUCTOR ===
Name: Esther
Age: 27
  

🔑 Keywords:

C++ constructor example, default constructor, parameterized constructor, copy constructor, OOPs in C++, class and object in C++, beginner C++ programs

📌 Hashtags:

#CPlusPlus #Constructor #OOP #CopyConstructor #ParameterizedConstructor #BeginnerCplusplus

🔍 Search Description:

This C++ program demonstrates how default, parameterized, and copy constructors work in object-oriented programming using class and objects with examples and output.