Lab 03

task1.cpp

#include <iostream>

class Rectangle {

private:
    double length;
    double width;
    bool error;

public:
    Rectangle() {
        this->length = 1;
        this->width = 1;
    }

    double getLength() {
        return length;
    }

    double getWidth() {
        return width;
    }
    bool isError() {
        return this->error;
    }
    Rectangle setLength(double length) {
        this->error = false;
        if (length >= 0 && length < 20 && length == (double) length) {
            this->length = length;
        } else {
            this->error = true;
            std::cout << "Please enter between 0 to 20, and should be float";
        }
        return *this;
    }

    Rectangle setWidth(double width) {
        this->error = false;
        if (width >= 0 && width < 20 && width == (double) width) {
            this->width = width;
        } else {
            this->error = true;
            std::cout << "Please enter between 0 to 20, and should be float";
        }
        return *this;
    }

    void calculatePerimeter() {
        std::cout << "Perimeter of rectangle is: " << 2 * (this->length + this->width) << std::endl;
    }

    void calculateArea() {
        std::cout << "Area of rectangle is: " << (this->length * this->width) << std::endl;
    }

};

int main() {
    Rectangle r =  Rectangle();
    double l, w;
    while (true) {
        std::cout << "Enter length: ";
        std::cin >> l;
        std::cout << "Enter width: ";
        std::cin >> w;
        r.setWidth(w).setLength(l);
        if (!r.isError()) break;
        else {
            std::cout << "Try again.";
        }
    }
    r.calculateArea();
    r.calculatePerimeter();
    return 0;
}

task2.cpp

#include <iostream>
#include <string>

class Invoice {
    private:
        double price;
        int num;
        int quantity;
        std::string desc;
public:
    Invoice(double price, int num, int quantity, const std::string &desc) : price(price), num(num), quantity(quantity),
                                                                            desc(desc) {}

    double getPrice() const {
        return price;
    }

    void setPrice(double price) {
        Invoice::price = price;
    }

    int getNum() const {
        return num;
    }

    void setNum(int num) {
        Invoice::num = num;
    }

    int getQuantity() const {
        return quantity;
    }

    void setQuantity(int quantity) {
        Invoice::quantity = quantity;
    }

    const std::string &getDesc() const {
        return desc;
    }

    void setDesc(const std::string &desc) {
        Invoice::desc = desc;
    }

    double getInvoiceAmount() {
        double res = this->quantity * this->price;
        if (res < 0 ) return 0;
        return res;
    }
};

int main() {
    Invoice i = Invoice(150, 645745, 6, "Sold");
    std::cout << i.getInvoiceAmount();
    return 0;
}

task3.cpp

#include <iostream>

class Data {
    int month, day, year;
public:
    Data(int month, int day, int year) : month(month), day(day), year(year) {}

    int getMonth() const {
        return month;
    }

    void setMonth(int month) {
        Data::month = month;
    }

    int getDay() const {
        return day;
    }

    void setDay(int day) {
        Data::day = day;
    }

    int getYear() const {
        return year;
    }

    void setYear(int year) {
        Data::year = year;
    }
    void displayDate() {
        std::cout << this->day << "/" << month << "/" << this->year;
    }
};

int main() {
    Data d = Data(6, 16, 2020);
    d.displayDate();
}

task4.cpp

#include <iostream>
#include <string>

class Employee {
    std::string fName;
    std::string lName;
    double salary;
public:
    Employee(const std::string &fName, const std::string &lName, double salary) {
        this->fName = fName;
        this->lName = lName;
        this->salary = (salary > 0) ? salary : 0.0;
    }

    const std::string &getFName() const {
        return fName;
    }

    void setFName(const std::string &fName) {
        Employee::fName = fName;
    }

    const std::string &getLName() const {
        return lName;
    }

    void setLName(const std::string &lName) {
        Employee::lName = lName;
    }

    double getSalary() const {
        return salary;
    }

    void setSalary(double salary) {
        this->salary = (salary > 0) ? salary : 0.0;
    }
};

int main() {
    Employee e1 = Employee("Ali", "Khan", 26656);
    std::cout << e1.getFName() << " " <<  e1.getSalary() << std::endl;
    e1.setSalary((e1.getSalary() / 100) * 10);
    std::cout << e1.getFName() << " " <<  e1.getSalary() << std::endl;
    Employee e2 = Employee("Usman", "Khan", 36656);
    std::cout << e2.getFName() << " " <<  e2.getSalary() << std::endl;
    e1.setSalary((e1.getSalary() / 100) * 10);
    std::cout << e2.getFName() << " " <<  e2.getSalary() << std::endl;
}