C++ Projects: Car Rental System

This system helps customers rent available cars. It maintains a list of different cars, their rental costs, and rental status. The system utilizes Object-Oriented Programming (OOP) concepts such as classes, file handling, and inheritance.

Features

• Adding new cars to the system.
• Displaying available cars and their rental status.
• Renting a car.
• Returning a car.
• Calculating the rental price based on rental hours or days.
• Saving rental car data to files.

Skills Used

• OOP Concepts: Classes, encapsulation, and different methods.
• File Handling: Saving and loading car data.
• Memory Management: Efficient handling of stored data.
• Vector Usage: Managing car data dynamically.
• Quality Assurance: Ensuring cars are rented and returned accurately.

Code Implementation

#include<iostream>
#include<vector>
#include<string>
#include<fstream>

using namespace std;

// Class to represent a single car
class Car {
private:
    int id;
    string model;
    string manufacturer;
    double dailyRate;
    bool isRented;

public:
    Car(int carId, string carModel, string carManufacturer, double rate)
        : id(carId), model(carModel), manufacturer(carManufacturer), dailyRate(rate), isRented(false) {}

    int getId() const { return id; }
    string getModel() const { return model; }
    string getManufacturer() const { return manufacturer; }
    double getRate() const { return dailyRate; }
    bool getStatus() const { return isRented; }
    void rentCar() { isRented = true; }
    void returnCar() { isRented = false; }

    void display() const {
        cout << "ID: " << id << ", Model: " << model << ", Manufacturer: " << manufacturer
             << ", Rate: $" << dailyRate << "/day, Status: " << (isRented ? "Rented" : "Available") << endl;
    }
};

// Class for managing the rental system
class CarRentalSystem {
private:
    vector<Car> cars;

    void saveToFile() {
        ofstream file("cars_data.txt");
        for (auto& car : cars) {
            file << car.getId() << ";" << car.getModel() << ";" << car.getManufacturer()
                 << ";" << car.getRate() << ";" << car.getStatus() << ";" << endl;
        }
        file.close();
    }

    void loadFromFile() {
        ifstream file("cars_data.txt");
        if (file.is_open()) {
            string line;
            while (getline(file, line)) {
                size_t pos = 0;
                vector<string> tokens;
                while ((pos = line.find(";")) != string::npos) {
                    tokens.push_back(line.substr(0, pos));
                    line.erase(0, pos + 1);
                }
                int id = stoi(tokens[0]);
                string model = tokens[1];
                string manufacturer = tokens[2];
                double rate = stod(tokens[3]);
                bool status = (tokens[4] == "1");

                Car car(id, model, manufacturer, rate);
                if (status) car.rentCar();
                cars.push_back(car);
            }
            file.close();
        }
    }

public:
    CarRentalSystem() { loadFromFile(); }
    ~CarRentalSystem() { saveToFile(); }

    void addCar(int id, const string& model, const string& manufacturer, double rate) {
        cars.emplace_back(id, model, manufacturer, rate);
        cout << "Car added successfully!" << endl;
    }

    void displayCars() const {
        if (cars.empty()) {
            cout << "No cars available in the system." << endl;
            return;
        }
        for (const auto& car : cars) {
            car.display();
        }
    }

    void rentCar(int id) {
        for (auto& car : cars) {
            if (car.getId() == id) {
                if (!car.getStatus()) {
                    car.rentCar();
                    cout << "Car rented successfully!" << endl;
                } else {
                    cout << "Car is already rented." << endl;
                }
                return;
            }
        }
        cout << "Car not found." << endl;
    }

    void returnCar(int id, int days) {
        for (auto& car : cars) {
            if (car.getId() == id) {
                if (car.getStatus()) {
                    car.returnCar();
                    double cost = days * car.getRate();
                    cout << "Car returned successfully! Total cost: $" << cost << endl;
                } else {
                    cout << "Car was not rented." << endl;
                }
                return;
            }
        }
        cout << "Car not found." << endl;
    }
};

int main() {
    CarRentalSystem system;
    int choice;
    do {
        cout << "\n=== Car Rental System ===" << endl;
        cout << "1. Add Car" << endl;
        cout << "2. Display All Cars" << endl;
        cout << "3. Rent Car" << endl;
        cout << "4. Return Car" << endl;
        cout << "5. Exit" << endl;
        cout << "Enter your choice: ";
        cin >> choice;

        switch (choice) {
        case 1: {
            int id;
            string model, manufacturer;
            double rate;
            cout << "Enter car ID: "; cin >> id;
            cin.ignore();
            cout << "Enter car model: "; getline(cin, model);
            cout << "Enter manufacturer: "; getline(cin, manufacturer);
            cout << "Enter daily rate: "; cin >> rate;
            system.addCar(id, model, manufacturer, rate);
            break;
        }
        case 2:
            system.displayCars();
            break;
        case 3: {
            int id;
            cout << "Enter Car ID to rent: ";
            cin >> id;
            system.rentCar(id);
            break;
        }
        case 4: {
            int id, days;
            cout << "Enter car ID to return: "; cin >> id;
            cout << "Enter number of rental days: "; cin >> days;
            system.returnCar(id, days);
            break;
        }
        case 5:
            cout << "Exiting... Bye!" << endl;
            break;
        default:
            cout << "Invalid choice. Please try again." << endl;
        }
    } while (choice != 5);
    return 0;
}

Real-World Examples and Case Studies

Enterprise Car Rental Systems

Major rental services like Avis, Hertz, and Enterprise use advanced systems to manage fleets across multiple locations. Features include:

• GPS tracking for rented vehicles.
• Integration with virtual booking systems.
• Dynamic pricing based on demand.

Ride-Sharing Services

Companies like Uber and Lyft offer rental services with advanced features such as:

• Automatic billing based on distance, time, and usage.
• User verification through ID and driver’s license.

Airport Car Rentals

• Fleet management for quick vehicle turnover.
• Integration with airlines for pre-booking.

Problem-Solving Approaches

• Fraud Prevention & Security: Encryption and OTP verification for customer data.
• Handling High Traffic: Database optimization and multi-threading.
• Scalability: Using unordered_map for efficient fleet management.

Thanks for reading! Gear up with your code editor and build something amazing!