2010 Lab-15

Lab elements include:
 • Polymorphism
 • Templates

Getting started
---------------

Do your work in your 2010/f directory.

Start with the following program.

Name it 2010/f/farm.cpp

//your name
#include <iostream>
using namespace std;

class Animal {
private:
    string name;
public:
    void makeSound() const {
        std::cout << "The animal makes a sound." << std::endl;
    }
};

class Cow : public Animal {
public:
    void makeSound() const {
        std::cout << "Moo Moo - the cow" << std::endl;
    }
};

class Chicken : public Animal {
public:
    void makeSound() const {
        std::cout << "cluck cluck - the chicken" << std::endl;
    }
};

int main() {

    return 0;
}

Follow along with Gordon to write the main() function.






Modify the farm program
-----------------------

    1. Add one or more animals to your farm.

    2. Add an array of animals to your main() function...

       Animal *farm[3];

       You finish the code to display each of your animals making their sound.

    Hints:
	    
       Allocate new memory for each of your farm animals.
       Use a for-loop to play the sounds of each animal.
       Don't forget to clean-up the allocated memory!

       If you get an error message when cleaning up the allocated memory,
       follow the suggestion given by the error message.

Here is some sample output... 

./a.out

On the farm...
 Moo moo - says the cow
 Cluck cluck - says the chicken

Array of animals
 Moo moo - says the cow
 Cluck cluck - says the chicken
 Quack quack - says the duck
 ???           says the pig
 ???           says the turkey
 ???           says the capybara
 ???           says the crow
 ???           says the frog




Write a templated function
--------------------------

Name your program 2010/f/template_sum.cpp

Start with the following program.

//your name
#include <iostream>
using namespace std;

int main()
{
    cout << "\nLab-15 template\n" << endl;
    cout << "sum of integers: " << sum(1, 2, 3) << endl;
    cout << "sum of chars: " << sum('j', 'k', 'l') << endl;
    cout << "sum of chars: " << sum<int>('j', 'k', 'l') << endl;
    cout << "sum of floats: " << sum(1.234f, 2.345f, 3.456f) << endl;

    return 0;
}

1. Write the templated function to make this program work.


Your output might look like this... 


./a.out

Lab-15 template

sum of integers: 6
sum of chars: A
sum of floats: 7.035



Why is the sum of 'j', 'k', and 'l' equal to A?




Add polymorphism to your mylab14.cpp program
--------------------------------------------

Copy your 2010/e/mylab14.cpp to 2010/e/mylab15.cpp.

Do this:

   cd 2010/e
   cp mylab14.cpp mylab15.cpp

Setup Vehicle class pointers to each of your base classes.

Maintain your program's original functionality.



Programs to be collected...
   2010/f/farm.cpp
   2010/f/template_sum.cpp
   2010/e/mylab15.cpp