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A very good way to shorten your lines of code in Python is by writing while or for loops.



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And this because if you want to print the large amount of numbers that's on your screen, you need to



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write so many print statements.



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If you want to print the numbers, you need to write the print statements.



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Right, so that you can use the while loop.



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So let's write I equals zero.



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OK, and here's how you write a while.



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So.



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Right, while I use more than or equal.



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Down five, so here we look while I is more or equal to five.



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OK, so while this is true, we want to print.



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Every night and then in the end, we can simply increment.



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I.



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I of course, I lost one here in that case, this means that in every law.



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So first I will be equal to zero, then it will be printed, it will be incremented by one, OK?



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And then the while loop will repeat and this will continue until I becomes equal to five.



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Then after it is equal to five, it will become equal to six.



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So loss is equal to six.



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This condition here will not be met and for that reason will get out of this law.



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So let's run our code now and see what happens.



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And you can see that we print all the numbers from zero to five, which is exactly what we expected.



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You can also go further by displaying not the numbers, but certain amount of character slips, right?



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Print I multiplication, same in here, we can write the symbol.



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So this means that for every loop we're going to type the symbol I as many times as the value of five



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is.



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So here's how this system go.



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So we can see here that in the final statement we have five, then we have four, three, two, and



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then only one.



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And this is how that while statement works.



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And there, as you can see, some different cases of what you can print or what you can do inside.



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Another very useful tool in any programming language in Python as well is the for loop.



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OK, so for loop usually loops around sets of numbers.



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Let's see.



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So for that reason I will create a list here and we're actually going to cover the list a little bit



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later as well.



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But here I will create a simple list of temperatures so temperatures will be equal to let's write five



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different temperatures.



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So the first one will be six, seven, then 30.



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Then seven two, then four to three, and finally 91.



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So this is the least of our temperatures.



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Then let's create a law that would prevent every of the temperatures in that list.



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So let's write for item in.



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Temperatures, so here you can see that item is for each item in the set of the temperatures.



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So for each of these values, we're going to do something inside the for loop.



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So what I will simply do here is to print the item or the current value that is taken from this set.



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So let's see what is going to be the result.



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Now, I think you can guess it, but yes, we'll get each of the temperatures on different line.



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OK, quite simple.



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And imagine if you have to do this with a while loop.



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We all need to write while and then for every step you need to increment the different position of the



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set and the loop will be way longer, actually double longer.



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Comparing to just for loop that we just wrote and for that reason sometimes is quite useful using the



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for loop in these cases.



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Another quite useful data structure for using in the Falu is the range.



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So I will actually change the temperatures here to a range of numbers and you can write.



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Numbers.



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Equals range then, and this means that here we're creating a range of numbers.



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OK, and we can see right here for each number in numbers, print number.



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OK, so in that way, we don't need to write every number, but we simply have the set of the numbers



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between zero and nine.



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OK, and we can print each of them.



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So if we simply press run us right or wrong, you can see that we have all the numbers here printed



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from zero to nine.



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So in the range we can do some actual quite fun stuff.



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So the first thing you can do is simply write two numbers here.



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So five and ten.



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And if you do this, you are simply going to get the numbers between five and 10.



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So you can also specify that the lower and the upper level.



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Then another thing you can do within the range structure is let's say you want to print some numbers



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between then.



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And 100, but also you want to print every five numbers, so here I write five.



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OK, and this is the increment between each number.



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So if I press here, you can see that we are getting excellent numbers between ten and nine to five



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or excellent between the 100th and that range, but the difference between them is five.



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So we get 10, 15, 20 and so on.



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And yeah, you can use the range in your advantage for four loops, which is quite useful then.