Welcome back.

How did you do on the challenge?

If you got the quiz working, good for you.

If you didn't, that's okay.

My programming challenges are becoming more difficult as I

teach you more JavaScript.

Let me show you how I programmed the quiz.

The first step is to create an array of questions.

Because I want to include a question and

an answer, I'll use a two dimensional array.

So each array inside the question array will contain two elements, a question and

its answer.

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I'll add a couple more questions.

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To keep the quiz simpler,

I'm just going to ask questions that have numbers for answers.

Because I want to keep track of how many questions the player answers correctly,

I'll need a variable to track correct answers.

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In addition, I'll define a few more variables.

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These variables don't have anything in them yet,

I'll fill them with values later.

But it's good programming practice to include variables at the top of

a script or for variables you use in a function at the beginning of the function.

That way, you or anyone else looking at your code can see in

a single place all the variables that are used in the script.

Now that we have an array of questions, it's time to ask them.

To do that, we should loop through the array, ask a question and

see if the player answers correctly.

I'll use a for loop for this.

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This should look pretty familiar to you by now,

it just creates a loop that runs as many times as there are items in the array.

I'm gonna pull some information out of each array item and

store it in a variable.

First, I wanna capture the question.

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Because this is a two dimensional array,

we first have to access an element from the outer array.

Then to access the question,

we have to get to the item at the first position, which is at the zero index.

The answer is at index one.

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Now we can ask the question and get a response.

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I didn't have to create this question variable,

I could've just added the array notation here like this.

However, I find it easier to read and understand my program if I used well-named

variables like question and answer and store the proper information in them.

Because the return value of the prompt dialog is always a string,

I need to convert it to a number.

This takes the value inside the response variable, converts it to a number,

then stores that number back into the response variable.

Here's a place I could shorten my code.

I could just wrap the parseInt method around the prompt method.

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With programming, you work your way out from the innermost set of parentheses.

For example, first we pass a string, the question, to the prompt method.

It returns a string value, which is then passed to the parseInt method.

I'll actually keep my code like this, I think it's simpler, and

easier to read, and I'll delete this line.

Our program isn't done yet.

But there's enough code here, that we can at least test to make sure that

the questions are being asked correctly.

I'll save the file and preview the workspace.

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So far, so good.

Now let's see if the response matches the answer.

We do this using a conditional statement.

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If the response does match the answer,

then we can increase the number in the correct answers variable by one.

Let's create a message and print it to the screen.

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All right, let's see how this works.

I'll save the file and preview the workspace.

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Awesome.

The quiz asks questions and keeps track of correct answers.

In the next video,

I'll present you with another challenge that will improve on this quiz.