All language subtitles for 17. Print Reversed Number - Solution

So let's dive into solving this exercise, so the first thing that we have to do is let's just make

it quick reminder of what we have to do is, for example, if we are getting a three digit number,

so five three one, for example, and what we want to do is simply to print the reverse number to the

screen.

So what we want to be printed is one three five.

And we said that there are two options to solve this exercise.

And one of the options is simply to find the units, to find the tents and also to find the hundreds.

And once we are successful, Honda, hundreds reds and once we've successfully managed to do it, we

can simply print the results to the screen.

So what do we mean by that?

Let's first of all, take a look at this main program.

We create here a new variable called NUM.

OK, we also create three additional variables that will assist us in the solution.

So in units, tens and hundreds, the units will represent the rightmost, the rightmost digit, the

dance will represent the middle digit and the hundreds will represent the hundred digits in these given

three digit number.

OK, so then we are going to print a little nice message for the user through the screen and a three

a three digit number.

We are going to read it using this kind of function in the percentage of the placeholder installed inside

of the address of variable NUM right after words we are going to use units equals to num model 10 to

find the right most digit in this case.

That's how we do it.

We already know it.

By now we find the terms and we find the hundreds.

So what we have here is let's see here is the number, which is five three one.

And also we have the units as one and the ten instance is three and the hundredth is five.

So basically one very simple solution that can be applied for this exercise is simply to print the result.

OK, the reverse number as the following, simply ride the printed function and use higher percentage.

OK, so let's say reverse reverse number, reverse number of percentage, the A's and here use percentage.

The percentage, the percentage then and I will explain right away what exactly do I mean.

So the reverse number of percentage then the first percentage is simply not right.

So that that's what we want to calculate the reverse number for basically to print.

So reverse number of percentage of NUM is OK.

So we want to display on the screen one three five.

So these percentages will be represented by the units.

So units and then the tens.

And then finally the hundreds.

So basically, if we will run this program right now, we know that previously we had like the leftmost

was the 100th.

And in this case it's the units.

The tenth remains in the same position.

And then the hundredth the previous hundredth is going to be now the units.

So we simply switched places.

But let's see what happens.

OK, if we build and run it.

So enter a three digit five three one, the reverse number of five three one is one three five.

OK, so pretty simple.

It seems to be working correctly.

Let's just make sure of it.

So eight, nine, seven, seven, nine, eight.

OK, so the units go to the goes to the hundreds and hundreds goes to the units.

The defense remains in its position.

So everything seems to be working correctly.

But if we wanted to take it even to the next level, because we kind of used here a nice trick to just

print the reversed value, but if we wanted to, let's say, to create a variable that will store it.

So, for example, if we have additional variable called reverse reverse now.

So how basically should we approach it?

We couldn't just take reverse num and say, OK, reverse now equals two.

I don't know, percentage.

The percentage.

The percentage.

Right.

This will be that would be a problem.

Percentage deep and just.

Here, unit.

It simply won't work.

What do we have to do is to apply some sort of mathematical operations and mathematical logic to calculate

the reverse?

None.

So what we know and that's very important to pay really close attention here, guys, because I'm going

to show you how to create these reverse numbers out of these numbers by using these units, tens and

hundreds in the way to do so is simply to understand that the previous units, one should become now

in the reverse number.

It should become the hundreds in the tens should we make tens and hundreds, should become just the

units and how should we basically constructed.

So I want to go with something like this.

OK, so let's just say reverse now equals to zero.

And I will say no, there was not actually there is no need to to nullify it.

So let's just say reverse now equals to what equals two units.

OK, so let's start with the reverse now equals to one in this case.

In our example then what I would like to say is to say reverse now equals to reverse number multiplied

by ten.

OK, plus the tenth.

OK, so I multiply these units by one because I need finally at the end that these units, that these

previous units, it will be multiplied by 100 because it will move from the units in the NUM to the

hundreds in the reverse now.

OK, so one should become one which was units, it should become hundreds in the reverse number.

And what we have to to understand here is that we have the reverse now multiplied by ten.

OK, we will still need to multiply it by another ten to get it, like to be multiplied by one hundred

plus tens.

So it will give us simply one multiplied by ten is ten plus stance, which is three.

It will give us for example, thirteen.

OK, but we are not finished yet because we simply added these tens as a units.

Right.

The three we need to add like 13, OK, to get our final result.

So then we take reverse now equals the reverse.

Now multiply by 10 once again.

That means that the units value the units that we took two lines before will be at the end multiplied

kind of by 800.

And the stance that we took in the previous line on the previous line will be multiplied by ten and

it will be in its right position.

So the units will be kind of treated like hundreds, the will be treated here as tens and we simply

should add the previous hundreds that should be treated in this line, in this reverse number as the

units.

So plus hundreds.

And basically what you will get is the previous reverse number, which is 13 multiplied by ten, which

is one hundred and thirty plus the hundreds, which in these cases five, which is one hundred and thirty

plus five, which gives us a final result of one thirty five, which is exactly the reverse number that

we wanted to find out.

So that was the first option by just printing it, kind of using percentage, the percentage, the percentage

and using the units, the tens and hundreds.

And another option is simply to just print out the reverse number, reversed the number of percentage

P equals two percentage D. And in this case, what we will use here is once again, here is the number

in the new created reverse num variable.

So let's try to build and run it and make sure that the results will be pretty much the same with using

using this additional calculated reverse num or without.

So let's go.

And five three one.

So one three five one three five.

Once again, let's use here on nine, eight, seven.

So seven, eight, nine.

And everything seems to be working just perfect.

Awesome.

So I hope you enjoyed this video that you liked the explanation, if you have any questions, feel free

to ask them.

Also, one last note for this video is that there are kind of plenty of exercises that rely on this

understanding of how to construct these reverse numb, because there may be exercises like write a program

that receives some number from the user.

The program should reverse the number and multiply it by five and multiplied by seven or add something

to it or dividing by something.

So that's something that you could not have used and correctly with this approach, with the first approach

that we use, just the units, tens and hundreds, as just the sequence of integers.

For that, you will have to calculate the actual result in the reverse num variable and then to continue

working with it and to continue applying on its different mathematical operations.

So, guys, this is it for this video.

My name is Vlad, this is Alphatech.

If you want to know more about the cause, the material things we're doing, watch and take a look at

the curriculum.

And also you will know what are the following chapters in these course?

What are the previous chapters?

Basically, this is it.

Thank you so much for watching.

I'll leave it with you.

Feedback and I will see you in the next exercises and then the next sections.

Until then, by.