Question

C#

The Zookeepers need a system to keep track of all their animals. They need to be able to enter all their animals into the system in a way that allows them to identify and locate them. This requires identifying them by species, age and one characteristic unique to their species.

• There are three cages and the user must input information about the animal in each one. After accepting input for all three cages, the program should output the contents of each cage in a way that exposes all the information about that animal.
• The program should accept the following species: Lion, Bear, Wolf.
• Define classes for the Lion, Bear, and Wolf species that all implement the Animal interface. All Animals should have an int field for age and a String field for species. Each species of animal should have its own unique field defined: String maneColour for Lions, int speed for Wolves, and bool isGrizzly for Bears. They should also define two methods:
  • RequestUniqueCharacteristic() which outputs a string asking for a value to store in the specific animal’s unique characteristic and stores it in the appropriate field (maneColour, speed, or isGrizzly)
  • GetDescription() which outputs a short sentence that includes all the animal’s info.
• Store all the Animals in a list of animals (List<Animal>) and iterate through the list to output all the animals after input is received.

Sample Session

Cage 1
What is the animal’s species? Lion
How old is it? 6
What colour is its mane? Brown

Cage 2
What is the animal’s species? Wolf
How old is it? 9
How fast can it run (in km/h)? 20

Cage 3
What is the animal’s species? Bear
How old is it? 12
Is it a grizzly bear (true/false)? No
=====
Cage 1 contains a 6-year-old lion with a brown mane.
Cage 2 contains a 9-year-old wolf that runs 20 km/h.
Cage 3 contains a 12-year-old non-grizzly bear.

Answer 1

The program is given below. The comments are provided for the better understanding of the logic.

using System;
using System.Collections.Generic;

public class Program
{
    public static void Main(string[] args)
    {
        //Declare the variables for holding temporary values..
        string species;
        string age;

        //Declare the animal interface
        Animal animal = null;

        //Declare the animals list.
        List<Animal> animalsList = new List<Animal>(3);

        //Start a loop 3 times to accept inputs of 3 cages.
        for(int i = 1; i <=3; i++)
        {
            //Get the inputs for species and age.
            string cageLabel = "Cage " + i;
            Console.WriteLine(cageLabel);
            Console.Write("What is the animal’s species? ");
            species = Console.ReadLine();
            Console.Write("How old is it? ");
            age = Console.ReadLine();

            //Depending on what species is entered, the below switch statement will instantiate a corrresponding class (Lion, Bear or Wolf)
            //It also calls the RequestUniqueCharacteristic method which will get the input of the unique characteristic
            //In case of wrong species is entered, the control will enter the default block and display an error message.
            switch (species.ToLower().Trim())
            {
                case "lion":
                    animal = new Lion(cageLabel, age, species);
                    animal.RequestUniqueCharacteristic();
                    animalsList.Add(animal);
                    break;
                case "wolf":
                    animal = new Wolf(cageLabel, age, species);
                    animal.RequestUniqueCharacteristic();
                    animalsList.Add(animal);
                    break;
                case "bear":
                    animal = new Bear(cageLabel, age, species);
                    animal.RequestUniqueCharacteristic();
                    animalsList.Add(animal);
                    break;
                default:
                    Console.WriteLine("Invalid Species");
                    break;
            }
        }

        //After all the inputs are received, display all the 3 cage and animal information.
        Console.WriteLine("=====");
        foreach (Animal a in animalsList)
        {
            a.GetDescription(); 
        }

        Console.ReadLine();
    }
}

//Create the animal interface as below.
//It has 2 abstract methods.
interface Animal
{
    void RequestUniqueCharacteristic();
    void GetDescription();
}

//The Lion Class is created as below.
class Lion : Animal
{
    private string cage;
    private int age;
    private string species;
    private string maneColour;

    //Default Constructor
    public Lion(string cage, string age, string species)
    {
        this.cage = cage;
        //The age is received as string from the main program.  Convert to int and store it in age.
        this.age = Convert.ToInt32(age);
        this.species = species.ToLower();
    }
    public void RequestUniqueCharacteristic()
    {
        //Get the unique characteristic of the animal.
        Console.Write("What colour is its mane? ");
        maneColour = Console.ReadLine().ToLower();
    }
    public void GetDescription()
    {
        //Display the short description about the animal.
        Console.WriteLine(cage +  " contains a " + age + "-year-old " + species + " with a " + maneColour + " mane.");
    }
}

//The Bear Class is created as below.
class Bear : Animal
{
    private string cage;
    private int age;
    private string species;
    private bool isGrizzly;

    //Default Constructor
    public Bear(string cage, string age, string species)
    {
        this.cage = cage;
        this.age = Convert.ToInt32(age);
        this.species = species.ToLower();
    }
    public void RequestUniqueCharacteristic()
    {
        //Get the unique characteristic of the animal.
        Console.Write("Is it a grizzly bear (true/false)? ");
        string characteristic = Console.ReadLine().ToLower().Trim();
        //The user can enter yes/no or true/false
        //Check it accordingly and store true or false in the field.
        if (characteristic == "yes" || characteristic == "true")
            isGrizzly = true;
        else
            isGrizzly = false;
    }
    public void GetDescription()
    {
        //Display the short description about the animal.
        //Depending on whether the bear is grizzly or not, display the information accordingly.
        if (isGrizzly)
            Console.WriteLine(cage + " contains a " + age + "-year-old grizzly " + species + ".");
        else
            Console.WriteLine(cage + " contains a " + age + "-year-old non-grizzly " + species + ".");
    }
}

//The Wolf Class is created as below.
class Wolf : Animal
{
    private string cage;
    private int age;
    private string species;
    private int speed;

    //Default Constructor
    public Wolf(string cage, string age, string species)
    {
        this.cage = cage;
        this.age = Convert.ToInt32(age);
        this.species = species.ToLower();
    }
    public void RequestUniqueCharacteristic()
    {
        //Get the unique characteristic of the animal.
        Console.Write("How fast can it run (in km/h)? ");
        //Convert it into int before storing
        speed = Convert.ToInt32(Console.ReadLine());
    }
    public void GetDescription()
    {
        //Display the short description about the animal.
        Console.WriteLine(cage + " contains a " + age + "-year-old " + species + " that runs " + speed + " km/h.");
    }
}

The screenshots of the code and output are provided below.