Original subtitles

All right, what is going on, guys, and this is a very interesting and very straightforward exercise

that will utilize the usage of recursion concept.

So what do we have to do here?

So let's start.

We have to write a function to we have to write a function that will do the following things.

First of all, this recursive function should get some integer value, let's say none.

OK, so the function is going to receive that will receive an integer value.

None.

OK, that's the first thing that our recursive function have to do.

Recursive, right.

We are talking about the recursion concept and we are going to use a recursive function.

So this function is going to receive NUM and the way the function is going to work is basically to receive

from the user a series of numbers of, let's say, natural numbers until the user will specify minus

one, for example, for the stopping condition.

So the function is going to read, let's say, a serious sequence of numbers from the user up until

up until up until receiving minus one.

And the function is going to return all of the numbers, basically not all the numbers.

The total amount of numbers which are smaller than OK, so return, the total number is smaller, smaller

than the value.

All right.

So let me discuss it.

Let me tell you a little example.

I think an example will be a good thing here.

So, for example, if you receive OK, if you receive now equals to five.

Oh, right.

And you have a sequence of numbers from the user alike, I don't know, six, eight, 10.

And then you have like three, one and seven and finally minus one.

Then in this case your recursive function should just return to OK, so the function should return to

why the function should return.

Return to is because on every time that you have read some value from the user.

OK, so you read the six, you read the eight, read 10, three one and so on and so forth, so on.

Every duration that you've read, not the duration actually, but on a recursive call, you checked

if a given number that you were reading is less than five, and if that's the case, you would simply

take these into account.

And finally return of the total numbers smaller than the naoum value than in this case, simply three

and five are smaller than some, not including the stopping condition, which is minus one.

And then basically you should return the value of two.

So I hope the instructions are clear to you.

And this exercise is not so trivial because I mean, there are a couple of things that we need to take

into consideration.

And one of these things is basically the fact that we don't really know in advance how many values the

user will insert.

Right.

We don't know if it will be one, two, three, five and so on and so forth.

OK, and the second thing that we have to take into consideration is the fact that we cannot use here

some standard while loop and to like read the values from the user, because that's the Terentiev approach

to solve this exercise.

But we want the recursive approach using recursive functions.

OK, so these are the two things that you have to bear in mind.

And also once we are going to start solving this exercise, what you also have to bear in mind is the

fact that you have to think of a way to construct these recursive function.

So you guys take your time.

Please take at least five, 10, even half an hour to think of this solution.

Try to write down everything on your on your own and to understand how you would have been you would

have implemented this on this function.

And until you do, I will be waiting for you and I will see you in the next video where we are going

to solve this exercise together.

So until then, good luck.