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[MUSIC]

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Hi everyone, this is James.

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In this C# practice session, you'll get
a chance to practice writing loops and

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conditional statements using C#.

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It reinforces what you'd learned in
stage three of the C# basics course.

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If you have a difficult time
completing this practice session,

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you might need to review that course.

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See the teacher's notes for a link.

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I have attached a workspace to his video.

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Go ahead and open the workspace or
download the project files

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if you want to use an external editor or
an IDE like Visual Studio.

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The program.cs file contains
a single main method.

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You'll write all of the code for
your program in this method.

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To complete this practice session,
read through the to-do code comments and

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complete each one.

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The purpose of this program
is to prompt the user for

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a number, calculate the square of the
provided number, and display the result.

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Let's see the completed program in action.

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First, we need to view the console.

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So, I'll click on View > Show Console.

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Remember, to compile a C# file,
we use the mcs command.

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Then, to run the program,
we use the mono command.

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See the teacher's notes, if you need
a refresher on either of those commands.

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Notice that the program prompts me for
a number, I'll enter 2.

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Then it displays the square
of my provided number.

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2 multiplied by itself is equal to 4,
we can enter another number.

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Or type the text quit to terminate
execution of the program.

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Let's review each of the to-do
comments in the program.cs file.

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Our first task is to declare a boolean
variable named keepGoing and

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assign it a value of true.

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You use these variable to know
when to exit the while loop.

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Speaking of the while loop,
your next task is to define a while loop.

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You want to keep looping as long as the
variable keepGoing has a value of true.

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Just inside of the while loop,
you want to prompt the user with the text,

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enter a number.

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And assign their value to
a string variable named entry.

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Then you'll want an if statement
that checks to see if the user

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entered the text quit.

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And if they did enter the text quit,
you'll want to exit the program.

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And if the user didn't
enter the text quit,

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you want to parse the users
entry to an integer.

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Then you want to take that number and
square it.

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You can do this by multiplying
the number by itself.

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Once you have the square of the number,
you want to output the result.

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So for example, output the text,
the square of 2 is 4.

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Or maybe 2 multiplied by
itself is equal to 4.

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Whatever you want to do,
the choice is yours.

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Then after exiting the loop,
let's output the text goodbye

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just to let the user know that
the program has finished running.

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Notice that the code comments are indented

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to reflect what the overall structure
of the program should look like.

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You can use this as a guide
when you're writing your code.

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If reading or writing to
the console is unfamiliar to you,

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be sure to review the second
stage in the C# basics course.

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Or see the teacher's notes for

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a link to another practice session that
will help you practice those skills.

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Okay, there is a lot here just take it
one step at a time, you've got this.

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And don't forget, practice is an important
part of the learning process.

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The more that you do the better that
your retention of the material will be.

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And if you get stuck at any point,
see the teachers knows for hands and

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links to videos.

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That cover what you need to know
in order to complete the session.

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And if you aren't able to fully
complete the program don't worry.

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I'll show you how I completed
the to-dos in the next video.

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Good luck and we'll see you in a bit.