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Okay, so from our scratch.java, I am happy
with how our multidimensional array works.

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So I'm gonna copy this and I'm gonna
move it into the explore file here.

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And let's drop that right here,

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underneath this friends array,
let's drop our scoreCards in.

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I'm gonna highlight these lines.

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And if you do Cmd or Ctrl+ bracket,
you can indent those to your liking.

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I don't know if I like that.

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I think that's lined up, there we go.

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All right, there we go.

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So let's take a moment to plan
out what we're about to do.

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Actually, before we do that,
I'm gonna get rid of this stuff down here.

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We don't need this anymore.

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Here we go, okay.

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So let's take a moment and
let's think about what we're gonna do.

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Now one thing that I find sorta helpful
is to write out your plan in pseudo code,

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which means more or less,
a code which you can translate later.

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Now if you do this in the form of single
line comments, some nice magic happens.

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So lets think this through.

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So let's see, we'll say for
each of our friends, so for each friend,

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we're gonna loop through them and
then we're gonna come in here and

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we'll say, we'll print their name, okay?

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And then for
each of those friends, for each

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hole that they've gone through say,
print their score.

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Make sense, right?

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So every friend, print their name for
each hole they had will print their score.

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So let's see.

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We have two arrays, one for
our friends and one for

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our scoreCards and
they just happen to line up right now.

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So let's use that to our advantage.

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Now, what I mean by line up is that
the first score card here is Ben's, right?

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And Ben is our first friend.

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So in deck zero of friends,
represents this friends' scorecard.

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And then Alena, is the second,
and that is this, so 1 and 2, 0,

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1, and 2, they all line up.

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So, let's loop through the friends, right?

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Let's do this, for
each friend let's loop through it.

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So, when you need an index, it's best
use the standard for loop, right?

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Just because we are gonna need this index,
so we'll say for the integer i = 0,

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that's where we wanna start,
we wanna start at the first one.

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And as long as it's less than length,

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get used to this pattern,
that's kind not look as tens and

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then we will move this all
the way down here to the bottom.

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Okay, and now we want to print their name.

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So let's say Sytem.out.printf,

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we'll do, %s.

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Do a new one.

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And hey,
why don't we also print out a separator?

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So we'll just draw something like this.

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So something to just mark
the screen up kind of nice.

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And so there, we wanna get the friends.

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So we'll use our index that we have, we'll
say friends i, to get that element for

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with this current loop
through the friends.

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Okay, so we can do this.

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So now we wanna loop this current
friends score for each hole.

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So we would show the whole number, so
we need to get the index again, so

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we'll say, for int, uh-oh.

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We're in a nested four loop here and

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we already have an i out,
it's in scope, right?

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So how do we keep these separate
in a different for loop,

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we can't use i cuz i already exists here.

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Well the good news is that this path
has already been blazed for us.

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This for loop inside of a for
loop is called nesting.

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Now you know that I really don't love
the short variable name of i, but

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it is standard practice so
we need to get used to it.

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Now something I like even less
is the common solution for

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the inner loop is to use the letter j.

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If there was another one,
it would be k and

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the next one in the nesting structure,
etc.

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Now this comes from the math world,
so we like to put the blame on them.

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So we're gonna loop just like this one.

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If the j = 0, I'm gonna initialize that,
and as long as j is less than,

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now we wanna make sure that we go
as long as there are holes left for

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this specific friend,
which is that index i.

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So we wanna go scoreCards and
we're gonna get this friends row of that.

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So that's this row here,
we'll say scoreCards

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[i].length, which in this
case they're all gonna be 18.

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And all of those written out there, but
we'll be careful, so we'll do this.

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And then I'm gonna wrap this, there we go,
and it says, print their score.

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All right, so we can do that,
we've done that before.

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So j is now our index into
each of these scores.

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So we have i for the row and
j for the scores.

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And that's handy because we need to get
a hold of each of these elements, so

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let's print their score.

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So much like before,
let's print out the whole number,

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so we'll say, System.out.printf, Hole,

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we'll say, %d and
then %d %n, for a new line.

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And we want to display
the whole number first, right?

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So that's what that first percent is,
so we'll say j, and

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remember it's zero based so
we need to add the 1, so j + 1.

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And now what we want is we want to pull
out of that multidimensional array what

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we're looking for.

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So we are gonna use the outer
loops variable of i and

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we want the current hole which is j.

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Cool, that looks nice and
that for loop closes out there.

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If you click here, that for
loop closes out there, awesome.

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What do you say?
Let's give it a try.

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So we'll say, clear and

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javac Explore.java and

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java Explore.

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I'm gonna pipe that into less just so
we can see better.

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Here we go.

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And there we go, here's bin, here's
a nice separator, here's bin scores,

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which let's just make sure is right,
1, 2, 4, 2, 6, 5 good.

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And if I press space bar it
will jump down or if I go down.

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So there's Alena, Alena is coming
up next and she's got 2, 3, 1, 5.

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Awesome, and then there's Pasan scores.

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We did it.

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There we go.

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For each friend,
we print out their name, and then for

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each hole, we print out their score,
just like our pseudo code, which,

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by the way, looks like the starts
of some great comments.

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Now, professionally, you wouldn't wanna
leave a comment at this code level because

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these are common patterns.

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But for now,

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comment away, this is a great way to
keep track all of that you are learning.

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Did that nested loop approach make sense?

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If it's still a little murky,

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why don't you give that a real watch
from when we added a pseudo code?

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Now remember,
please speed me up if you need to.

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If you need to, slow me down.

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Now it might sound like I've had a few,
just know that I haven't.

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But I would like to celebrate
with you because you are cruising

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through this course.

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Multidimensional arrays are hopefully
starting to feel a lot less outer spacey.

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They're handy for
your row and column needs.

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You're really starting to see
how great arrays can be, and

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now I need to show you the bad stuff,
and how to deal with it.

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Now, arrays have some limitations,
and it's time we dealt with them.

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Now, don't worry,
I'll show you workarounds and

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also some more cool tricks that you can do
with them, right after this quick break.