FizzBuzz!

Quick reference

• 00:04 In this video I want to talk about FizzBuzz.
• 00:06 And FizzBuzz used to be an old interview question that you would get when you
• 00:10 went into a coding job.
• 00:11 And it was a good question because you can do it in just about any
• 00:14 programming language, and it's a good way to sort of gauge what you know.
• 00:18 So we're going to step back now and take a little bit of a review of
• 00:21 all the stuff we've learned up until now and use it to create this FizzBuzz.
• 00:24 So the idea of FizzBuzz is pretty simple.
• 00:27 We want to print all the numbers to the screen between 1 and 100.
• 00:30 And if a number is divisible by 3, we want to print out the word Fizz.
• 00:35 If a number is divisible by 5, we want to print out the word Buzz.
• 00:39 And if a number is divisible by both 3 or 5, we want to print out FIZZ BUZZ.
• 00:44 So think about this, how would you do this yourself?
• 00:47 kind of try and think it through before we try it in this video.
• 00:49 You're going to obviously need a loop because we're going to have to
• 00:52 loop through between 1 and 100.
• 00:53 You're going to need to determine if a thing is divisible by a number.
• 00:57 That seems like sort of a job for a modulus.
• 00:59 And then we're going to have to do certain things based on that.
• 01:02 And that sounds like conditional statements, if and else if statements.
• 01:06 And we're testing against multiple things so
• 01:08 we're probably going to need an else if in there or maybe two.
• 01:11 So try and think it through and do it yourself.
• 01:13 But we're going to go ahead and right now just do it here.
• 01:15 So the first question to ask is what type of loop should you use?
• 01:18 And it absolutely doesn't matter one bit.
• 01:20 I probably would do a while loop because I like while loops,
• 01:23 but we were just talking about an each loop.
• 01:24 So let's start out with an each loop and end it.
• 01:28 And let's just puts out x.
• 01:31 So we have a range between 1 and 100.
• 01:33 And for each of those numbers, we want to do something with this variable x.
• 01:38 So let's save this and run it.
• 01:39 And I'm a big fan of making little incremental bits of code and
• 01:43 then testing them to see if they work.
• 01:44 So we can see this is printing out to 100, so that seems to work.
• 01:47 So now, let's start out by knocking out the big hard thing.
• 01:51 Determining if the number is divisible by both 3 and 5 at the same time.
• 01:55 And that seems like a job for a multiple conditional statement.
• 01:58 So let's go if x modulus 3 equals 0 and
• 02:02 x modulus 5 equals 0, then let's puts out x,
• 02:07 but we want to do some other stuff.
• 02:10 So let's do our interpolation.
• 02:13 And let's go x and let's put a period next to it just for
• 02:16 formatting to make it look nice.
• 02:17 And if it's divisible by both 3 and 5, we want to print out FIZZBUZZ.
• 02:21 So let's go FIZZBUZZ, right?
• 02:25 That looks good.
• 02:26 Now, this is the multiple conditional.
• 02:28 Let's break apart each of these two, the 3 and the 5,
• 02:32 and create a conditional statement for those.
• 02:35 And so of course we're going to use else if for that.
• 02:37 So else if x divisible by 3 equals 0.
• 02:43 And I'm just going to copy this line.
• 02:49 So if it's divisible by 3, we want to print out the number plus the word fizz.
• 02:52 I'm just going to delete that buzz there.
• 02:55 Let's put an exclamation mark just for fun.
• 02:58 So that handles the 3.
• 02:59 Now let's do the 5, same thing.
• 03:01 We'll just do another else if x modulus 5 equals 0.
• 03:06 And, again, I'm just going to paste this in and delete the fizz.
• 03:10 So if it's divisible by 5, we want to print out BUZZ.
• 03:13 Otherwise, we just want to print out the number.
• 03:15 So let's just go else and then do the same thing.
• 03:20 So that should just print out the number.
• 03:23 So finally we need to end our if statement.
• 03:25 So this end goes with this if.
• 03:27 This end goes with our loop.
• 03:29 And if we're lucky, go ahead and save this and run it and it looks pretty good.
• 03:34 So let's scroll back to the beginning.
• 03:37 So we have 1, 2, 3, 3 is divisible by 3, so it prints out FIZZ.
• 03:42 4, 5, 5 is divisible by 5, so we get BUZZ.
• 03:46 Up through here, and 15 is the first instance where it's divisible by both
• 03:50 3 and 5, so we get FIZZBUZZ.
• 03:52 And we just sort of eyeball this, scroll through here, 30 again,
• 03:55 we get another FIZZBUZZ, and it looks like it worked correctly.
• 03:59 All the way up to 100 which is divisible by 5 and we get BUZZ.
• 04:02 So that's FizzBuzz, very simple little program, very small,
• 04:06 just a few lines of code, but there's a lot of stuff packed in here.
• 04:09 Multiple conditional statements, modulus, else if, got our loop going on.
• 04:13 It's a good way to sort of practice some of the stuff we've done up until now.
• 04:16 So take a few minutes and try and redo this with a different type of loop.
• 04:20 And maybe try and do it with less lines of code, see if you can do that.
• 04:23 And it's just a really good way to kind of practice some of the stuff
• 04:26 we've learned up until now.
• 04:27 So that's FizzBuzz.
• 04:28 In the next video, we're going to look at hashes.

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