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For this project, you had to create
a function to build an array

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of ten random numbers between one and 100.

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Then you had to call that function
to create an array, then use a for

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loop to access each item in that array.

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Now, we provided the function for
the random number generator.

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If you want to brush up on
the Math.random function,

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check out the teacher's notes for links.

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Let's start by creating
the shell of the function, and

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we'll name that function createRandomList.

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I'll type function createRandomList,
a set of parentheses, and a set of braces.

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Now I'll start by creating an empty
array to hold the random numbers.

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I'll call it randomList.

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In order to add ten random
numbers to the list,

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I'll create a loop that runs ten times and
uses a counter variable named i.

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Now each time through the loop,
the i counter increments by one.

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That's this i+=1 part.

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Now a shorter way to
write that is just i++.

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++ is an incremental operator,
and just adds 1 to the variable.

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Now, if you're bit rusty on for
loops, see the teachers notes, for

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a link to more instruction on them.

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Now within the loop,
I'll call the random 100 function, and

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store the results into a temporary
variable called randomNumber.

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Then to add the number to the randomList
array, just use the array push method,

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like this.

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Type the array name, randomList.push,

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and then I pass randomNumber,
that's the variable.

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Now you could actually
simplify this code a bit,

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you don't need this
randomNumber variable at all.

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It simply holds a value,

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the same value that's returned when
the randomNumber function is called.

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You can skip the variable, and

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simply call the randomNumber
function like this.

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Now outside the loop, we want to return
the ten item random list variable.

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Let's try out this
function by calling it and

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storing the results into a new
variable named myRandomList.

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Type let myRandomList =
createRandomList() with

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a set of parentheses to call the function.

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To see if it worked,
let's log the array to the console.

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I'll type console.log(myRandomList).

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Let's save the file.

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And use node to run it in the console,

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by typing node 2_loop.js.

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And there you have a ten item array.

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How do we know that they're random?

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Well, let me call it again and let's see
if we get different numbers, and we do.

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If your program isn't working, double
check against the code in the teacher's

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notes below and
try to figure out your error.

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Now, the last part of this project is
to use a for loop to iterate through

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the array and print the elements
one line at a time to the console.

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First, I'll add the basic format for
a for loop.

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Now, this loop will run ten times.

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That's fine in this particular case
because the array has ten items, but

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it's not very flexible.

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It'd be better to run this loop
the same number of times as there

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are elements in the array.

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Fortunately, we can get the number of
items in an array using an array's

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length property.

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So just replace 10 here
with myRandomList.length.

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Okay, let's log a string to the console.

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Inside the loop, I'm just gonna
type console.log to begin with.

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Let's just print out a simple string,
Item 0 in the array is 48.

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Let's see what happens,
I'm gonna save this file.

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Clear my console and
run the program again.

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Well, [LAUGH] that isn't very helpful
cuz it prints the exact same string

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over and over again.

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So let's make this a little bit
more tailored to our array.

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So I'm gonna change this 0,

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and using string concatenation,
I'll add our i counter.

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Let's see what happens now.

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A little bit better.

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So we see the index increasing,
0, 1, 2, 3.

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But we're always getting the same number.

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So what we need to do now
is access the element

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at the same index value within the array.

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And we can use the i counter to do that.

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Use string concatenation one more time

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to access myRandomList
at the i index value.

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Let's save this file, Type clear,

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And run this one more time,
and there it is.

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If you had trouble with this
practice session, don't worry.

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Compare your code to the code listed
in the teacher's notes below.

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Look very carefully at
what tripped you up.

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Study it and
figure out how to fix your code.

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Failure is the best way to learn, and

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we don't usually get things
right on the first try.

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As you'll learn later, there are other
array methods that can help you achieve

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similar results, like the for each method.

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As always in programming,

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there are often many different
ways to solve the same problem.

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Ready for the final practice challenge?

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I’ll see you in the next video.