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<v Jonas>All right, here goes coding challenge number two,</v>

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which is gonna be all about arrays.

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And in this one,

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we're gonna go back to the tip calculator

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that we built in the previous section.

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And we're still using the same rules as before.

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So we tip 15% of the bill value, if it's between 50 and 300.

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And if the value is different, so outside of this range,

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the tip is 20%.

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And so here are your tasks.

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First, write a function called calcTip,

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which takes any bill value as an input,

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and returns the corresponding tip.

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And so that's gonna be based on the rules

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that I just mentioned.

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And to do this, you can actually check out the code

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from the first tip calculator challenge

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that we did in the last section.

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So you can copy the code there.

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Or if you want, you can also code this from scratch,

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just to remember how to do it.

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And now in number two, we're finally gonna use arrays.

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So here, we're gonna create an array called bills,

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which will contain the test data that we have down here.

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So these are the three bill values

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for which we want to calculate the tips.

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And so that's what we do in point number three.

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So here, we create an array called tips,

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which will contain the tip value

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for each of the three bills.

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And this is where we're gonna use the calcTip function

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that we created before.

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So that's the basic challenge.

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And if you wanna take it one step further,

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you can even take the bonus question.

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So number four here,

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in which I ask you to create an array called total,

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which will have the total values.

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So that's the bill plus the tip.

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So I hope this one isn't too hard.

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Basically, it's similar to one of the examples actually,

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that we did in one of the lectures about the arrays.

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And once again,

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I also have a hint to help you solving this one.

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But if you want to try it on your own without the hint

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then pause video now, and good luck.

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But if you want to hint,

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well, then here it goes.

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So remember that an array needs a value in each position.

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But that value

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can actually be the returned value of a function.

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So as an array value,

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you can basically just call a function. Alright.

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And again, that is similar

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to something that we did in one of the array lectures.

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So pause the video now,

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and I see you with my solution in a second.

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Okay, and I'm gonna start by creating the calcTip function.

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And I'm gonna start doing it with a function expression.

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So this one will receive a bill as an input,

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I believe, I think,

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yeah, so calcTip takes any bill as an input.

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So let's simply call it bill.

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And then what we want to return is the tip.

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And here I'm gonna write the exact same code

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as we did in the other challenge.

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So there's no need to explain it all again,

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it would just be a waste of time.

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So if the bill value is between 50 and 300,

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so less or equal than 300.

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And here we're using the ternary operator,

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then return the bill value, times zero point 15.

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So that's 15%.

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And otherwise, it should be 20%.

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Okay, so the result of this ternary operator here

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will be one of these values.

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So either bill times point 15 or times point two.

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And so that's gonna be the result of this operator.

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And so that's what this function will return.

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If you prefer the arrow function, we can also do that.

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So const calcTip equal bill.

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And now we can omit the return keyword

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and do it all in one nice line.

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So now you just have to choose which one you like better.

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And I will just for the sake of readability.

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Keep the first one there. Okay.

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But if you prefer the arrow function,

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you can just use this one. Great.

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So number two is to simply create a bills array

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with these three values.

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So bills 125, five five five and 44.

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So that was easy.

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And now we will create an array tips,

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which will contain the tip value for each bill.

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So, let's do that.

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And now this is similar to what we did previously

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with calculating the ages.

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So we are going to create an array,

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and then each position will be the function call to calcTip.

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So we want to calc the tip with bills at position zero.

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Then at position one, we want to calculate bills.

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Or we actually want to calculate tips based on bills

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on position one, and then on position two. And that's it.

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So let's log both the bills

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and the tips to the console here.

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And that gives us tips is not defined.

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So here, it should be tips.

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So usually when I have an array,

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I like to give it a plural name,

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like here bills and here tips.

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So because it's multiple values,

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so now that should work.

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And yeah, so these were the three tips that were calculated.

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And of course, you could have created separate values,

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or actually separate variables

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for each of these function calls,

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like tip one equals calcTip with bills, zero,

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something like this.

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And then tip two and tip three.

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And then you could have created

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like an array with tip one, tip two and tip three.

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Okay, so something like this.

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But my idea was to actually do it like this,

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because then we don't have to create

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all these extra variables. So that's a lot cleaner.

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Later on in the section,

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we will find an even better way of doing this.

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But with what we know, at this point,

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this is the best that we can do.

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So we take the first bill,

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calculate the tip based on that

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and put it in position number zero,

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then we take bills at position number one

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calculate the tip and put it in position one

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of this new array,

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and then we take bills at position number two,

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calculate the tip

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and put it at position two of the new array.

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And so then, now we end up with this.

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Lastly, let's also complete the bonus question

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number four here.

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And all you have to do here is to create an array,

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which will have the sum of the bills and the tips.

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So that's gonna be totals.

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And now you might have tried to do something like this.

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So like bills plus tips.

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But as I told you in the previous lecture,

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this is simply not gonna work.

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So we cannot do any operations on arrays like this,

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it doesn't work like that.

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So let me show you the result that we would get

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from doing this.

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And so basically, each of the arrays would be transformed

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to a string, and then the two strings would be concatenated.

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So that's completely useless.

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And so the only thing that we could do

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is to say that we want bills at position zero,

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plus the tips at position zero.

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And now we do this for all the three values.

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So at position one as well.

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And then at position two.

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And so this fixes this error, because now in each position,

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we do actually have a real value,

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because this is an actual value.

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And so with that, we can then do calculations.

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So, yeah, this is correct. Looks correct. Right.

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And yeah, so with that, all of the four points are solved.

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And so here we conclude this part about arrays