oop.cpp

#include <iostream>
#include <string>
using namespace std;
// Object-Oriented Programming (OOP) in C++

// Abstraction
class Car
{
public:
    void start()
    {
        cout << "Car started" << endl;
    }
};

int main()
{
    Car myCar;     // creating an object of the Car class
    myCar.start(); // calling the start method to start the car
    return 0;
}

// Inheritance
class Animal
{
public:
    void eat()
    {
        cout << "Eating..." << endl;
    }
};

class Dog : public Animal
{ // Dog class inherits from Animal class
public:
    void bark()
    {
        cout << "Barking..." << endl;
    }
};

// Polymorphism
class Shape
{
public:
    void draw()
    {
        cout << "Drawing a shape..." << endl;
    }
};

class Circle : public Shape
{ // Circle class inherits from Shape class
public:
    void draw()
    { // overriding the draw method of Shape class
        cout << "Drawing a circle..." << endl;
    }
};

// Default Constructor
class Person {
public:
    string name;
    int age;

    Person() {   
        cout << "Enter name: ";
        cin >> name;

        cout << "Enter age: ";
        cin >> age;
    }
};


// Parameterized Constructor
class Rectangle {
public:
    int width;
    int height;

    Rectangle(int w, int h) { // constructor with parameters
        width = w;
        height = h;
    }

    int area() {
        return width * height;
    }
};


//Function Overloading
class Math {
public:
    int add(int a, int b) { // function to add two integers
        return a + b;
    }

    double add(double a, double b) { // function to add two doubles
        return a + b;
    }
};


//Operator Overloading
class Number {
public:
    int value;

    Number(int v)
    {
        value = v;
    }

    Number operator+(Number n)
    {
        return Number(value + n.value);
    }
};


// Polymorphism
class Base {
public:
    virtual void display() { // virtual function for polymorphism
        cout << "Base class display function" << endl;
    }
};

class Derived : public Base {
public:
    void display() override { // overriding the display function of Base class
        cout << "Derived class display function" << endl;
    }
};


//Data hiding
class Account {
private:
    string accountNumber;
    double balance; 
public:
    void setAccountNumber(string accNum) {
        accountNumber = accNum;
    }
    void setBalance(double bal) {
        balance = bal;
    }
    string getAccountNumber() {
        return accountNumber;
    }
    double getBalance() {
        return balance;
    }
};