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You have completed Feeling Loopy with Java!
You have completed Feeling Loopy with Java!
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Do While loops are a post-check looping construct, they will run at least once.
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All right, so.
0:00
While loop.
0:01
We checked before hand, right?
0:02
I wouldn't of had to keep on asking that,
0:03
wouldn't have keep on doing that
loop if I didn't ask for it.
0:05
Now let's do a do while loop, okay.
0:07
So a do while loop.
0:09
It's the same concept, right.
0:10
We don't know how many times
it's going to happen but
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we do know that we want
it to happen one time.
0:12
Right, so
it does what's called a post check.
0:14
So this is useful when you want to
make sure that one time it happens.
0:17
So.
The example that I have for this,
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we're totally shifting examples here.
0:23
The example that I have for this one,
this pseudo code is Mini-Golf, right?
0:24
So, you can't get a hole in zero.
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You have to get a hole in one, right?
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That's the best you can do.
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So you gotta putt once, okay?
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So we're gonna say do.
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Where, is the ball in the hole
is a Boolean over here.
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I should've said, is the ball in the hole?
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See, I'm bad at pseduo-code.
0:41
And we do puttPutt.
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We're gonna call and
see if we hit that ball in the hole and
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until here, that's actually, while not.
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Right?
In English, too, if you wanted to say,
0:50
until something happens, you're really
saying, wow, this isn't happening.
0:52
Right?
So, until is a verb, or a whatever
0:55
type of word that is in other programming
languages is a keyword in other type of
1:00
programming languages, and it really means
while not, but Java does not have that.
1:04
So we're gonna do, well, let's code it.
1:08
So cross your fingers for me, here we go.
1:11
Some more live code.
1:12
All right.
1:14
So, mini golf.
1:14
All right, so I imported something that
we probably have not talked on yet.
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It's handy for testing and
example things like this.
1:22
It's randomness, right.
1:24
It's gonna allow us the ability
to give a 50/50 thing, right.
1:26
So I don't know about you but
my mini golf skills is not 50/50,
1:29
I usually have about 99, you know I
take a very long time to go through.
1:32
So what we'll do is we want one time,
we want to do a putt putt.
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And let's keep track of it so
that we can see how bad we did.
1:40
Or how bad the computer did,
actually, right?
1:44
So we're gonna do numberOfPutts.
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Such a weird word, you know, how like
when you're typing words and you're like,
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is that really how you spell putt?
1:51
I don't know.
1:52
And putts, too, like.
1:53
All right.
1:54
So, boolean ballInHole is gonna be false.
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We're gonna start out with it false,
right?
1:59
So the do while loop,
we're gonna say do while, and
2:01
this is where we're doing the end tells,
so not the ballInHole, right?
2:05
So it's a little strange, right?
2:10
So you're thinking,
while the ball isn't in the hole,
2:12
while that's not true,
keep on looping, okay?
2:14
Let's just print out something so
we know that we're put that's not great.
2:17
Alright.
2:24
So let's use that random generator.
2:25
And I called that thing luck,
2:28
I called the variable luck, which is what
you need when you're doing this stuff.
2:30
And it has random has
the opportunity to return numbers or
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other random things, one of the things
that can return is a Boolean.
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And remember, Booleans are true or false.
2:41
We're setting ballInHole to the Boolean,
so therefore when it comes to check,
2:44
we'll see, we want to increment.
2:47
I don't know if everybody knows
what this incrementing is or
2:49
if we remember what that is.
2:52
What it does is it basically is shorthand
for saying, I could say number of putts
2:54
equals what number of putts was plus one.
2:57
So it just takes whatever's in there and
adds one to it.
3:03
It's a shorthand.
3:06
Let's keep it in there.
3:07
We're gonna talk about that
a little bit later, too.
3:09
All right.
3:13
For sure one time it goes through.
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It will at least be one, right?
3:17
Cuz they tried one time.
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And if the ball went in the hole,
it would be over, and good job,
3:19
we did a hole in one.
3:22
But we'll say, you got it in %d,
because it's a number.
3:23
And we're gonna pass n
the number of putts.
3:31
What do you say?
3:34
I remember that.
3:38
Let's do it.
3:40
I don't know where my history went.
3:42
Let's see.
So we'll call this Minigolf.
3:46
We're gonna compile Minigolf, and
then we are going to run Minigolf.
3:48
Don't put the Java extension there.
3:53
One, hole in one, we did it randomly.
3:58
We randomly did a hole in one!
4:00
>> [APPLAUSE]
>> Yeah!
4:02
Still, a hole in one.
4:03
Come on, oh there it is.
4:05
Three putts.
This should.
4:06
Wow, it's doing pretty good.
4:10
>> Looks good.
4:11
>> There's two putts.
4:12
Yeah.
>> [LAUGH]
4:13
>> Yeah.
4:14
Let's go golfing and
4:14
let's put some money on it.
Cool.
4:15
>> [LAUGH]
4:17
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