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Now we're moving on to conditional statements now you could give conditional statements as an if else

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scenario.

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For example if you go to the store and you want to purchase a drink and the drink cost two dollars.

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Well if you have two dollars you're going to be able to purchase that drink.

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If you don't have two dollars then you won't be able to purchase that drink.

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That is a condition.

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So the condition there is based on the amount of money you have.

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We can take these conditional statements and we can run if else we could also run if else if else and

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build upon these.

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Now it all makes sense when we start putting it together in our script here.

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So let's go ahead and just do that let's make a new line and let's make a comment here that says conditional

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statements.

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And let's start with a conditional statement.

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So a conditional statement is going to start off looking like a function.

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So we'll say define and here let's make the same scenario where we talked about the money and buying

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into ring.

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So we'll define drink and we'll just say a parameter here of money.

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OK.

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And then let's invent and let's say if money is greater than or equal to to me where we talked about

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two dollars for this drink then we're going to return.

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You've got yourself a drink.

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Now what if we don't have the money.

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So we could say else if our money is not greater than or equal to two then we're just going to return

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no drink for you didn't mean to capitalize the o there but I'm leaving it because I like it.

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So in this situation we have our conditions set.

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Now again if our money equals or EAP is equal to or greater than two we're gonna get a drink.

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And if not we're not going to get a drink.

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So it could be anything else.

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Right.

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So what we can do now is since this is just returning and not printing anything we can print out something

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like a drink and then we specify the amount.

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So if we have three we should return one thing.

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And if we print drink here with only a dollar we should return another.

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Let's go ahead and save this script and I didn't put this with an ampersand so I'm going to close out

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and make sure I do that next time.

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And we're gonna do is we're just going to go ahead and Python 3 script up high and you can see down

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here we go back and let me run this script with the ampersand.

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You can see that we did a drink of three which we were expecting to return.

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You've got yourself a drink.

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And we did a drink of one which we're expecting to return no drink for you this happened just the way

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we thought it would.

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So we can build upon these conditional statements.

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Let's talk about a different scenario with multiple parameters.

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Let's say that you are an adult and here in the United States if you're an adult and you want to have

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a drink of alcohol that requires you to be of age at twenty one.

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So in order to purchase alcohol you have to be one of age and to have money.

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Now if you don't drink that's perfectly OK.

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This is just a example scenario.

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So here let's say we wanted to buy alcohol.

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We have to meet that age requirement of 21 and we have to meet the requirement of money.

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Now we could be in a situation where we meet the age requirement but we don't meet the money or we could

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meet the money requirement.

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But we don't meet the age requirement or we could be in a situation where we don't meet the age requirement

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and we don't meet the money requirement.

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So let's set this up to think through this and how these scenarios could play out.

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So let's define alcohol here and we need two parameters we're going to say age and money

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so first statement here is gonna be our leading if we're going to say if age is greater than or equal

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to 21 because we need that condition to be true and our money is greater than or equal to 5.

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So let's say a drink cost five dollars we're going to return

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we're getting a drink

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OK now since we're gonna have multiple conditions here we're going to introduce something called else

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if.

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Else if here is written like this.

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E L I F so else if our age is greater than or equal to twenty one and R money is less than five dollars

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then let's return

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come back with more money.

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We need another else here because we have another condition right.

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So we're gonna say whatever our age is less than twenty one and our money is greater than or equal to

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five.

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Well we're going to return.

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Nice try kid because we're not old enough to purchase this drink.

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And then lastly and our else scenario if we are not meeting any of the conditions above which means

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we won't have the age we won't have the money then we're just going to return here to like a type sorry

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you're too poor and too young so let's go ahead and run this a couple different times.

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So let's go ahead and print out alcohol and we're going to give our two parameters let's say twenty

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one in five let's print out again alcohol and let's give a parameter of twenty one and four and then

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let's print out one last time of alcohol and we'll say that we are 20 and four so we should meet a few

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different conditions here.

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Right.

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So at twenty one in five we should return we're getting a drink at 21 and four we should return come

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back with more money and at 20 and 4 we should return.

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You're too poor and too young.

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Now if you want to add in a fourth condition here or a fourth print statement and you want to return

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the Nice try kid you're more than welcome to do that as well.

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So go ahead.

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Hey control ask or save your script out and then let's go ahead and run it

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and you can see it we return exactly where we thought we're going to.

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We're getting a drink.

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Come back with more money and you too poor and too young.

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So this is it for conditional statements.

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Hopefully this makes sense again our conditions are based on certain items.

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Right.

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So money here for an example if we have the money we're getting a drink.

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If we don't have the money we're not getting a drink and then we can build upon that we have multiple

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parameters here.

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So if we're not old enough to buy a drink or we don't have enough money to buy a drink or we don't meet

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any of these scenarios different things can happen.

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Well you need to be thinking about as a developer program or even writing these scripts is all the scenarios

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that could happen in these situations you've got to think of the logic behind it.

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So when you're building out a script you're building out your first program.

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You need to think logically if I make an if statement or a conditional statement what's the logic behind

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it.

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So a lot of times for example in this scenario we might have thought OK well if I don't have that The

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Age or the money OK but you've got to think about what if I do have the age but not the money or I do

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have the money but not the age.

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So you have to think through everything in your head and make sure that it's all thinking and this just

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takes repetition.

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And just sitting down the best way is sitting down at the pen and paper and not writing this in code

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form but this writing this in a sense that makes sense to you.

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Thinking through it logically and then writing it out in code.

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So from here we're going to go ahead and move on to list in the next video.

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So once you are caught up here let's go ahead and move right over there.