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Okey dokey, what is going on, ladies and gentlemen, and welcome to another very interesting yeah,

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not so easy exercise using recursions.

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And in this video, in this exercise, what you are going to do is basically to write some very nonintuitive

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function.

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And it's going to simply do to take you now, hopefully to to the next level, because this exercise

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is very not straightforward.

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And actually I kind of consider it to be much more complex than the previous exercises, at least then

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the exercises you solved at the beginning of this section.

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So without further ado, let us start working.

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So what do you have to do in these exercises to write a function, a recursive function, so write a

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recursive function that gets some, I don't know, natural number and at least function basically should

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be, first of all, a recursive function and it should get some natural number.

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And OK, so far, so good.

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And now what the function has to do is let's say you have some number and you also know that this number

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is compromised of digits.

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Let's say I don't know and equals two, three, six, four, three, five, OK, something like that.

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And you know that this is a number and this number is compromised of digits.

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So you have the digit at index zero.

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OK, well, we'll start from right to left.

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OK, so the position of each digit in a number, we will assume that it has some index that we will

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be able to refer to.

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I don't know if index is the appropriate word for it, but let's say position.

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OK, so a digit has a position and we start the position right from zero.

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OK, so these five is a budget position zero.

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This three is a digit at position one.

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These four is a digit at position two and so on and so forth.

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So let's just write it down because that's an example.

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I'm trying to build it and to explain it also to you as we go so and equals two, three, six, four,

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three, five.

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So we will say that position zero, the number is five.

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Position one, the number is three position position to the number four.

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Position three, the number is six.

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And position polarization for the number is three.

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OK.

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Awesome.

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So that's basically of introduction to what we are going to do in this exercise.

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So we get some number and it's a natural number.

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And what we want to do is to make sure that every digit OK in a are in an even location has an even

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value.

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OK, and also that every digit in an odd location has an odd value.

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OK, so for example, if you have this number, OK, so three six four three five, we will look at

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all of its digits.

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So we will start with digit with the first digit at position zero and we see that the position is even

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but the number itself, the value is odd.

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OK, and our position one, the position itself is odd and the value is also odd.

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So we want this function to return return one.

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If every digit

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gets a at and even position has an even value as well as every digit at an odd position has an odd value.

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Otherwise return zero.

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OK, so that's otherwise.

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And basically, what I mean by that is that for this example, the result will be zero because not every

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even position there is an even value.

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OK, so this is an even position, but the value is odd.

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So that's very simple.

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The result should be false, basically should be zero.

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So let's see another example and let's say we have, I don't know, some simpler, simpler example.

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So example number two, and it goes like this.

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So for three and let's say eight.

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So position zero has a value of eight.

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Position one has a value of three and position two has a value of four.

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And in this case, we will see that an even position, the reason even value it, even position there

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is an even value and also at all the position, we have an odd value.

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OK, so that's basically what we have for this example example, number two will have like return one

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and for the first example, we will have to return zero.

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OK, so that's the exercise.

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Not so easy, not so trivial.

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You have somehow to distinguish between many different options and many different possible numbers that

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you have to take care of and how basically you find this position using some recursive approach, although

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the the Terentiev approach using sound for a while loop, many seem a little bit easier to solve this

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exercise, but that's not what we are here for.

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Basically, we are here to solve it on using the recursive approach, the recursive concept and using

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this recursive recursion function.

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OK, so think about it, how you can solve it even even.

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I don't know.

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Let's try even to take a few hours.

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If you still don't get like the perfect result that works for all of the numbers you are trying for

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all of the natural numbers you were trying either.

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These numbers are going to be one digit, two digits, three digits, five digits and so on and so forth.

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OK, so take some time.

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Think about it, even if you can solve it in a few hours.

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Don't leave this exercise.

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Don't jump straight to the solution.

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Try to solve it on your own.

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It's very important that it's not a trivial that's not an easy exercise and it's mandatory for you to

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give it a shot on your own and to try to become a better programmer, because that's the process and

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that's the way guys who.

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So I hope everything is clear to you.

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Let me know if you have any questions about this exercise and hopefully you will manage to solve it

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on your own and then to compare it with my solutions.

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If not, of course.

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Please, after that, take the solutions video and make sure that everything is clear to you and that

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you are capable of proceeding further.

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So thank you guys for watching.

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My name is what this is Alphatech and we are going to solve it together.

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So let's go.