Question

Codes: (car.h ; car.cpp ; carDemo.cpp)

/*
-----------------------
Car
-----------------------
- make: string
- year : int
-----------------------
+ Car()
+ setMake(m: string) : void
+ getMake() : string
+ setYear(y: int) : void
+ getYear() : int
----------------------
*/

#ifndef CAR_H
#define CAR_H
#include <iostream>
using namespace std;

class Car {

private:
    string make;
    int year;

public:
    Car();
    Car(string);
    Car(int);
    Car(string, int);
    void setMake (string);
    string getMake() {return make;}
    void setYear (int);
    int getYear() {return year;}

};
#endif


#include "Car.h"
#include <iostream>
#include <cstdlib>
using namespace std;

Car::Car() {
        make = "";
        year = 0;
}

Car::Car(string m) {
        make = m;
        year = 0;
}

Car::Car(int y) {
        make = "";
        year = y;
}

Car::Car(string m, int y) {
        make = m;
        year = y;
}

void Car::setMake (string m) {
        make = m;
}

void Car::setYear (int y) {
        year = y;
}


#include "Car.h"
#include <iostream>
using namespace std;

int main() {

        Car myCar;
        myCar.setMake("Toyota");
        myCar.setYear(1999);

        cout << myCar.getMake() << " " << myCar.getYear() << endl;

        Car myCar2("Ford");
        cout << myCar2.getMake() << " " << myCar2.getYear() << endl;

        Car myCar3(2016);
        cout << myCar3.getMake() << " " << myCar3.getYear() << endl;

        Car myCar4("Honda", 2005);
        cout << myCar4.getMake() << " " << myCar4.getYear() << endl;

        return 0;
}

Using the previous code for the Car Class, implement this UML:

/*
-----------------------
          Car
-----------------------
- make: string
- year : int
- speed: int
-----------------------
+ Car(string, int)
+ setMake(m: string) : void
+ getMake() : string
+ setYear(y: int) : void
+ getYear() : int
+ setSpeed(s: int) : void
+ getSpeed() : int
+ accelerate() : void
+ brake() : void
----------------------
*/

Note that there is only one constructor which receives arguments for and sets the make and year. Have your constructor then set the speed to zero.

Note the two new member methods: accelerate and brake. Accelerate should increase speed by 5, and brake should decrease speed by 5. Note that your speed can never be a negative number, so ensure that your method definition guards against that by outputting an error message.

Write a demo program that exercises this class. Create a car object, accelerate it, brake it, exercise it. Have your class definition also print out the "state" of the object after each acceleration or braking. Sample output:

Accelerating...
Toyota | 1998 | 5
Accelerating...
Toyota | 1998 | 10
Accelerating...
Toyota | 1998 | 15
Braking...
Toyota | 1998 | 10
Braking...
Toyota | 1998 | 5
Braking...
Toyota | 1998 | 0
Braking... Error: can't brake a car that's standing still.
Toyota | 1998 | 0

Answer 1

Here is the completed code for this problem. Comments are included, go through it, learn how things work and let me know if you have any doubts or if you need anything to change. If you are satisfied with the solution, please rate the answer. Thanks

//Car.h file

#ifndef CAR_H

#define CAR_H

#include <iostream>

using namespace std;

class Car {

private:

    string make;

    int year;

    //new attribute

    int speed;

public:

    Car(string, int);

    void setMake(string);

    string getMake() const { return make; }

    void setYear(int);

    int getYear() const { return year; }

    //new methods

    int getSpeed() const { return speed; }

    void setSpeed(int s);

    void accelerate();

    void brake();

};

//overloading << operator to display state of the Car

ostream& operator<<(ostream& out, const Car c)

{

    out << c.getMake() << " | " << c.getYear() << " | " << c.getSpeed();

    return out;

}

#endif

//Car.cpp file

#include "Car.h"

#include <iostream>

#include <cstdlib>

using namespace std;

Car::Car(string m, int y)

{

    make = m;

    year = y;

    speed = 0;

}

void Car::setMake(string m)

{

    make = m;

}

void Car::setYear(int y)

{

    year = y;

}

//new method implementations

void Car::setSpeed(int s)

{

    //setting speed only if it is non negative

    if (s >= 0) {

        speed = s;

    }

}

void Car::accelerate()

{

    cout << "Accelerating..." << endl;

    speed += 5;

}

void Car::brake()

{

                //displaying error if speed is 0

    if (speed == 0) {

        cout << "Braking... Error: can't brake a car that's standing still." << endl;

    }

    else {

                //braking and decrementing speed by 5

        cout << "Braking..." << endl;

        speed -= 5;

        //if speed went negative, making it 0

        if (speed < 0) {

            speed = 0;

        }

    }

}

//CarDemo.cpp file

#include "Car.h"

#include <iostream>

using namespace std;

int main()

{

                //creating a Car

    Car myCar("Toyota", 1998);

    //accelerating and displaying state for 3 times

    for (int i = 0; i < 3; i++) {

        myCar.accelerate();

        cout << myCar << endl;

    }

    //braking and displaying state for 4 times

    for (int i = 0; i < 4; i++) {

        myCar.brake();

        cout << myCar << endl;

    }

    return 0;

}

//OUTPUT

Accelerating...

Toyota | 1998 | 5

Accelerating...

Toyota | 1998 | 10

Accelerating...

Toyota | 1998 | 15

Braking...

Toyota | 1998 | 10

Braking...

Toyota | 1998 | 5

Braking...

Toyota | 1998 | 0

Braking... Error: can't brake a car that's standing still.

Toyota | 1998 | 0