Description

1. Write C++ programs
2. Compile C++ programs
3. Implement programs that involve method method overriding, and polymorhpism.

Additional Reading

This lab exercise requires an understanding of some concepts to solve the problems. You are strongly encouraged to read the following tutorials to help you answer the problems.

1. Organizing C++ files: function prototypes, implementations, and drivers.
2. Using objects as parameters and return values in functions
3. Passing arrays as parameters to functions
4. File reading and writing (also includes dealing with arrays)

Instructions

Answer the programming problems sequentially (i.e., answer prob01 before prob02). If you have questions let your instructor or the lab assistant know. You can also consult your classmates.

When you answer two programming problems correctly, let your instructor know and wait for further instruction.

Lab exercise guide

Here’s a link to the Lab exercise guide in case you need to review the lab exercise objectives, grading scheme, or evaluation process.

Driving management software

You will be creating a base class Car and two derived classes GasolineCar and ElectricCar. The user interface is mostly implemented for you. The focus of this exercise is to demonstrate polymorphism through virtual functions and pointers to derived classes.

Car class

This class is almost complete so you only need to implement two functions: drive and is_empty. However, here is a rundown of the member functions you will have to use/create.

Data members

Create a class called Car. It will have the following data members

1. name_ which is an std::string that will be the name of the car
2. year_ which is an int that will be the manufacturing year for that car
3. speed_ which is a double that will be the current speed of the car

Member functions

Public Methods

default constructor

1. name_ should be initialized to "Steam automobile".
2. year_ should be initialized to 1769
3. speed_ should be initialized to 0

non default constructor

The constructor initializes the following variables

For parameters it needs:

1. std::string name for the name of the car.
2. double year for year if the car.

and it initializes the member variables name_ and year_ with these parameters. additionally, speed_ gets initialized to 0

accessors

Create functions that will return each of our data members.

1. std::string name() returns the name_ of the car
2. int year() returns the year_ of the car
3. double speed() returns the speed_ of the car

mutators

Create functions that will modify the member variables

1. void set_name() sets the name_ of the car
2. void set_year() sets the year_ of the car

drive

Receives a single double parameter that sets the speed_ of the car according to the value provided. This should be a virtual function that derived classes can use/override.

is_empty

Define this as a virtual function that always returns false. It will be overridden in the derived classes.

ElectricCar class

Data members

Create a class called ElectricCar

It will be a class we create that inherits from the Car class. It will have one additional data member

battery_percentage_ which is a double that represents the battery percentage.

Member functions

Public Methods

non default constructor

The constructor initializes the following variables

For parameters it needs:

1. std::string name for the name of the car
2. int year for the year of the car

and it initializes the appropriate member variables with these parameters. additionally it sets speed_ to 0, and sets battery_percentage_ to 100.0

default constructor

The default constructor should set name_ to "Electric carriage", year_ to 1832, speed_ to 0 and battery_percentage_ to100.0.

bool is_empty()

Returns true if battery_percentage_ is 0.

drive(double speed)

This override function will perform two steps.

1. IF the battery percentage is above 0, then it should call drive from the Car object and update battery_percentage_. The value subtracted from the battery percentage is equal to (speed/4). Specifically, battery_percentage_ -=(speed/4)
2. IF the remaining battery_percentage_ after Step 1 has fallen to or below 0, then call Car‘s drive method to set its speed to 0.

GasolineCar class

Data members

Create a class called GasolineCar It will be a class derived from the Car class and has two additional data members.

1. tank_ which is a double that represents the number of gallons a car’s fuel tank can store.
2. mpg_ which is a double that represents the miles per gallon a car can travel.

Member functions

Public Methods

non default constructor

The constructor initializes the following variables

For parameters it needs:

1. std::string name for the name of the car
2. int year for the year of the car
3. double tank for the amount of fuel this car can store
4. double mpg for the fuel efficiency for this car.

and it initializes the appropriate member variables with these parameters. additionally it sets speed_ to 0.

default constructor

The default constructor should set name_ to "Gasoline car", year_ to 1885, tank_ to 12, mpg_ to 24, and speed_ to 0.

bool is_empty()

Returns true if tank_ is 0.

void drive(double speed)

This override function will perform two steps.

1. IF the amount of fuel left in the tank_ is above 0, then it should call drive from the Car object and update tank_. The value subtracted from tank_ is equal to (speed/mpg_). Specifically, tank_ -=(speed/mpg_)
2. IF the remaining amount in tank_ after Step 1 has fallen to or below 0, then call Car‘s drive method to set its speed to 0.

Other instructions

Complete the main function as described. Place your classes in car.hpp. Member functions that take more than five lines or use complex constructs should have their function prototype in car.hpp and implementation in car.cpp.

Sample Output 1

Ubiquitous on-board driving management software test: - Gas/battery level sensor -
What type of car is being tested?
1 - Gasoline Car
2 - Electric Car
0 - Exit
1
What is the name of the car? Toyota
What year is the car? 1996
How many gallons of gas can this car store? 13
How much MPG does this car have? 27
How fast do you want to drive this car for an hour? 50
It took Toyota about 8 hour(s) of driving to empty the tank

Sample Output2

Ubiquitous on-board driving management software test: - Gas/battery level sensor -
What type of car is being tested?
1 - Gasoline Car
2 - Electric Car
0 - Exit
2
What is the name of the car? Tesla
What year is the car? 2017
How fast do you want to drive this car for an hour? 60
It took Tesla about 7 hour(s) of driving to empty the battery

Submission checklist

1. Created function prototype and stored in .hpp file.
2. Created function implementation and stored in .cpp file (see reference).
3. Call function in the driver
4. Compiled and ran the driver (main).
5. Manually checked for compilation and logical errors.
6. Ensured no errors on the unit test (make test).
7. Followed advice from the stylechecker (make stylecheck).
8. Followed advice from the formatchecker to improve code readbility (make formatcheck).

Code evaluation

Open the terminal and navigate to the folder that contains this exercise. Assuming you have pulled the code inside of /home/student/labex02-tuffy and you are currently in /home/student you can issue the following commands

cd labex02-tuffy

You also need to navigate into the problem you want to answer. To access the files needed to answer problem 1, for example, you need to issue the following command.

cd prob01

When you want to answer another problem, you need to go back up to the parent folder and navigate into the next problem. Assuming you are currently in prob01, you can issue the following commands to go to the parent folder then go into another problem you want to answer; prob02 for example.

cd ..
cd prob02

Use the clang++ command to compile your code and the ./ command to run it. The sample code below shows how you would compile code saved in car.cpp and main.cpp, and into the executable file main. Make sure you use the correct filenames required in this problem. Take note that if you make any changes to your code, you will need to compile it first before you see changes when running it.

clang++ -std=c++17 main.cpp car.cpp -o main
./main

You can run one, two, or all the commands below to test your code, stylecheck your code’s design, or formatcheck your work. Kindly make sure that you have compiled and executed your code before issuing any of the commands below to avoid errors.

make test
make stylecheck
make formatcheck

A faster way of running all these tests uses the all parameter.

make all

Weapons classes

This program uses four classes: Weapon, Dagger, ShortSword, and Enemy. Implement the classes in weapons.hpp and weapons.cpp.

Weapon class

Create a Weapon class with the data members int attack_min_, int attack_max_, and std::string name.

Create a default constructor for Weapon that sets the attack_min_ to 1, attack_max_ to 2, and name_ to "weapon"; in that order.

Create a constructor that receives two ints for attack min and max, and an std::string for its name.

Create accessors for all data members.

Create a virtual function attack that returns an int representing the amount of damage done by the weapon. The math for the attack function should be: (random_number % (max - min)) + min

Random numbers can be generated by calling the rand() function that is declared in the random header. That is, you need to #include <random>.

Daggers class

Create a Daggers class with data members int crit_, and int crit_dice_. Daggers inherit from Weapon.

Create a default constructor for Dagger that will set attack_min_ to 2, attack_max_ to 3, and the name_ to "daggers". It should also set crit_ to 1, and crit_dice_ to 18.

Create a constructor that receives two ints for attack_min_ and attack_max_, an std::string for the name_, an int for crit_, and an int for crit_dice_. Take note that you can call Weapons constructor.

Create accessors for all data members.

Unlike the usual Weapon that only computes damage once, daggers can do damage twice and also have a chance to critically damage an enemy. See the details below to get the value returned by attack().

Damage 1:

1. Compute damage the same way as the Weapon‘s attack function: (random_number % (max - min)) + min.
2. Randomly generate a number between 1 and 20. If the number is greater than or equal to crit_dice_ then multiply the damage from step 1 by the value of crit_.

Damage 2:

1. Compute damage the same way as the weapon‘s attack function: (random_number % (max - min)) + min.
2. Randomly generate a number between 1 and 20. If the number is greater than or equal to crit_dice_ then multiply the damage from step 1 by the value of crit_.

The attack() function should return the sum of damage 1 and damage 2 described above. Take note that damage 1 and damage 2 could produce different values.

ShortSword class

Create a ShortSword class with the data member int multiplier_. ShortSword inherits from Weapon.

Create a default constructor for ShortSword that sets attack_min_ to 6, attack_max_ to 7, the name_ to "shortsword", and multiplier_ to 1.

Create a constructor that receives two ints for attack_min_ and atack_max_, an std::string for name_ and a int for the multiplier_.

Create accessors for all data members.

Override the attack function to provide a damage multiplier. The steps below describe how to compute the output of the function.

1. Compute damage the same way as the Weapon‘s attack function: (random_number % (max - min)) + min.
2. Randomly generate a number between 1 and the multiplier_ (for example, 1 to 4 if the multiplier is 4). The function should return the damage multiplied to the randomly generated number.

Enemy class

Create an Enemy class with two data members, an std::string name_, an int health_.

Create a default constructor for Enemy that sets name_ to "dragon" and health_ to 500.

Create a constructor that receives an std::string name and int health the assigns it to the data members accordingly.

Create a function called receive_attack that receives a pointer to a Weapon object. Call the Weapon object’s attack function and reduce the Enemy‘s health by that damage, then print out the damage statement: <weapon> dealt <X> damage to <enemy>. If the enemy takes lethal damage, print out: <enemy> has been slain! (replace the values inside < > with the actual values of the object). See the output below to see an actual example.

Other instructions

Complete the main function as described. Place your classes in weapons.hpp. Member functions that take more than five lines or use complex constructs should have their function prototype in weapons.hpp and implementation in weapons.cpp.

Sample Output:

Please enter the name of an enemy: goblin
Please enter the enemy's health: 10
daggers dealt 4 damage to goblin
shortsword dealt 6 damage to goblin
goblin has been slain!

Submission checklist

1. Created function prototype and stored in .hpp file.
2. Created function implementation and stored in .cpp file (see reference).
3. Call function in the driver
4. Compiled and ran the driver (main).
5. Manually checked for compilation and logical errors.
6. Ensured no errors on the unit test (make test).
7. Followed advice from the stylechecker (make stylecheck).
8. Followed advice from the formatchecker to improve code readbility (make formatcheck).

Code evaluation

Open the terminal and navigate to the folder that contains this exercise. Assuming you have pulled the code inside of /home/student/labex02-tuffy and you are currently in /home/student you can issue the following commands

cd labex02-tuffy

You also need to navigate into the problem you want to answer. To access the files needed to answer problem 1, for example, you need to issue the following command.

cd prob01

When you want to answer another problem, you need to go back up to the parent folder and navigate into the next problem. Assuming you are currently in prob01, you can issue the following commands to go to the parent folder then go into another problem you want to answer; prob02 for example.

cd ..
cd prob02

Use the clang++ command to compile your code and the ./ command to run it. The sample code below shows how you would compile code saved in weapons.cpp and main.cpp, and into the executable file main. Make sure you use the correct filenames required in this problem. Take note that if you make any changes to your code, you will need to compile it first before you see changes when running it.

clang++ -std=c++17 main.cpp weapons.cpp -o main
./main

You can run one, two, or all the commands below to test your code, stylecheck your code’s design, or formatcheck your work. Kindly make sure that you have compiled and executed your code before issuing any of the commands below to avoid errors.

make test
make stylecheck
make formatcheck

A faster way of running all these tests uses the all parameter.

make all