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was going on guys and welcome to your twenty-fifth C plus plus tutorial and in this tutorial. 
And in this tutorial, I going to be 
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talking to you guys about
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a really cool feature of c plus plus, not only C plus plus,
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this is basically an all computer programming languages, but it's called
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the switch statement.
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in the switch statement, in your computer programming career,
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is going to save you a whole lot of time and headaches.
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so let me give you guys an example of when you would use this
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say you have a variable like age. And you want to test age of a user
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and
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and you had a bunch a different uhm,
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like statements you want to print out depending on how old they were. So, if
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they were 16,
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uhm, you'd say "congratulations here's a new car
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since you can drive now" or 18 you would say, "go buy a lottery ticket"
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if they're 21, you say "go buy some beer" so you have
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all these different values that you could have applied applied to the same variable.
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so with our knowledge so far we can build program like this
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doing this. if age equals 16
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let's go ahead and type our body and then after this
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if age equals this yadda yadda equals that
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well all those if statements are getting pretty old, so wouldn't it be cool
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if we could combine this all and kind of a compact
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statement? well it would be cool. but, unfortunately we can't. So, on to the next
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tutorial in the next tutorial.
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I'm just kidding. we actually can do this and that is through the use of something
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called a switch statement.
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now in order to use a switch statement here's what you do.
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type the word "switch" now in parentheses right after that
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write the variable that you want to test. well, we want to test the value
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age so it go ahead and type age right there. now after this
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go ahead and add the body to your statement. now inside your body
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you going to give all the values which you think
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age is equal to. And we are going to be giving it in the form of cases.
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so, pretty much for saying this. In case they enter sixteen
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but don't write in case. It's only case, so in the case
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of sixteen. Then write ":". now after this colon, 
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you write whatever statements you want your computer program to perform
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or computer program to perform. you are the computer programmer.
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this is computer programming. There, I got straight in my brain. so
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in case the value of age equal 16, let just go ahead and put something stupid down
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screen like
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 cout "hey you can drive now"
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and go ahead and end line. why not.
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and after this add a key word that says  "break". Now
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I'm going to be talking about break later on, because it's easier if I
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make the whole program first before I talk about it. now after this we can
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write something like alright,
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what if the case is 18? and what are we going to print out then?
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uhm cout on the screen. uhm
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"go buy some lotto
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tickets" because you can do that 18.
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now in line and of course after this at that break statement that we
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don't know what does yet but we will. and let's go ahead give it one more case, why not?
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And the case of
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21, the best one, uhm, let's go ahead and
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cout "buy
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me some beer" and go ahead and that line, so
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now you can see, through the use of the switch statement, it
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basically saved us the trouble and the time up making a bunch
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of different if statements. So instead of three different if statements,
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fuh, fuh, fuh, there different statements we only had one switch
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and we just tested a bunch different cases. so the last thing
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is "default" what default means, is if none of these cases were true
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if they entered value like two or something like that.
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It ran through all these cases. was equal to 16?
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nope. 18? nope. 21? nope. so what you want me to perform
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by default? and of course you don't need like default too because
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it doesn't have a value. it just all these values failed
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then what do you want me to do by default. by default which is write cout
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uhm, sorry
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you get nothing because 16, 18, 21,
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Thats reality, where the important stuff happens. everything else is just birthday
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so let's go ahead and end that line. And, one thing you might notice
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uhm, when we build and run this, and alright,  uh sorry you get nothing, because
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you're too boat. Before you go and don't run this
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"why do you I had a break at the end of default? and what exactly is break?
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well, this break keyword right here pretty much means
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end the switch. So you are saying "alright". why would I want to end it?
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why doesn't it just keep going through the rest of the stuff?
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well the reason you add break after each case is because this:
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say you had 16? and you want to test it.
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we know that whenever ran it printed out,
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hey you can drive now. and that's because we tested age
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and age is equal to 16. so in our first cases it says hey
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this is a match, let's go ahead and run this bit of code right here
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so since we got a match in our first case,
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there's no need to test this one, this one, and we know we're not going to run the
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default, because
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this is the only one we want to run right here. So, what break says
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is break this switch. it pretty much saves your program the trouble of having to
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run through the rest of these cases.
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because it's not going to be
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useful to run through the rest from as soon as he found a match.
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so let's go ahead and say we had 18 in there. well what we would do is
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it runs it and it prints out "go buy some lotto tickets"
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since we have that break in there, it did  this, alright,
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in the case of 16, nope you're 18, and the case have 18,
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bingo we have a match. so let's go ahead and print out "go buy some lotto tickets"
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and break out of this loop. so no need to test 21,
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and no need to use the default, since we broke out of it.
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we found our match. so, again what break does
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is it basically saves you from going through the rest the loop.
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and why do I not have one and default because
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by the time we get to the end default it said and that the switch anyway so
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why would you need to break out if you just can exit out of it after the
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default anyways.
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so that is basically a switch statement
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It basically takes a variable and tests the value against
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each one of its cases. 16, 18, 21
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if it isn't any one of those values it runs the default.
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now I have three cases in this example, but you can have one.
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you can have a thousand. you can have a million if you want.
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and yeah, that's all. so anyways,
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that is how a switch works and that is what break is.
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And, I just want to mention one more thing before I let you guys go.
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break, I'm using it in this example of a switch
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but, it is a key word, that  we are goint to be coming across a lot in C++ programming
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not only with switch.  So, whenever you see it later on, whenever we're doing
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you know just regular loops or something, I just want to let you guys know
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it just isn't only limited to switch statement. we can actually use this
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all throughout C++. So, whenever you come across it, don't be like hey, isn't a 
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switch supposed to be going around that, because
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we're not. so now, thank you guys for watching. 
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understand the switch and once you do you're ready to move on to my next video.
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so
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thank you guys for watching. Don't forget to subscribe. And I will see you in the next video.