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ok so lets talk about that sneaky

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method i mentioned it does involve

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thinking about things slightly

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differently and a clue again was in that

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comment that i added down here in line

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42 unless the final character in the

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string was a period so the question is

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what would happen if we made sure that

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the final character in the input string

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was a period

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well two things would happen the for loop

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would always execute at least once

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because there would be at least one

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character in the input string also would

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be no need for that final test because

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if the final character is a period than

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the previous segments details would

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always be printed so let's see how that

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would actually work

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first I'm going to start by commenting

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out this final if statement and

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also going to comment out the

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initialization to the character variable

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on line

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32 now if we're making sure that the for

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loop executes at-least once then we

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don't need to make sure the character

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has a value so that's why I'm commenting

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that out so at this point we really need

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to do is append a full stop

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sorry period to whatever the user types

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in so down here under line 28 i'm going

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to type....

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and again I won't run through all the tests

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because I've done that and with one

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exception they all produce exactly the

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same results I will make sure that running

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the program and entering blank input works

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so lets do that

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press enter we are now correctly getting the

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message segment one contains zero

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characters whereas before course we need

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that optional code on line 44 and 45 to

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get that working let's also try single

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segment I'm going to run it again and

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just enter 8 for the input segment one

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contains one character that also works

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and try...

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that's also working but the exception is

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any input that already ends in a period

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so if we actually run that again

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....and again a period on the

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end

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so you got segment 1234 which is

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correct but this modified program now

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displays the results for a fifth segment

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containing 0 characters now that's

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arguably more correct but if you want

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exactly the same behavior as we had

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previously then you just check that the

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input string didn't already end with a

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full stop then only trying to append one if it

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didn't

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the important thing here though is

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thinking about the problem slightly

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differently can lead to simple code now

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we haven't covered how to check the last

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character in the string so don't

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worry about that bit i'm going to make

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the change to check the final character

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just to satisfy the curious so let's go

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ahead and do that so up here we're

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going to change this code and put....

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....

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....

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....now we'll be covering

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that in the course soon if you run that

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again

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...we now

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correctly get the results and the fifth

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segment is now no longer showing that's

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because we're only adding the period if

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it is not already one there now before i

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finish this video there is one more

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thing that I want to mention and I'm

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sort of Crow barring this in here

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because it was covered in the previous

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version of this video and incidentally

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I re recorded this video and

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the previous one

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after listening to comments from

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students so I'm going to make a slight

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change to the code so that i can still

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cover this next bit so forgive me if

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this is a slightly contrived way to lead

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into it so what we are going to do is copy the

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description on IP address from the

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comment on line 4 here and paste it

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into the input prompt on line 28

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going to copy the entire line

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copy and I'm gonna replace it here

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on line 28 I just removed the word but

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for simplicity so i'll end up with a

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full stop like you can see that so what

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we've done is we've made the message a

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little bit more informative so that we

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can have a look at why we don't get a

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green tick at the top-right of our code

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window anymore and also take the

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opportunity to clear up some of these

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lines down the end just leave the one

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line down the bottom and we got our

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green tick now intelliJ tries to make

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life easy by highlighting all

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occurrences of variables etc so you may

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find that there are a lot of markers on

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the right-hand side of the code window

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for example if you click on the word

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segment on line 32 i'll do that now

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notice how we now got segment

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showing in a number we got the

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markers on the right-hand side now

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that's because intelliJ will highlight

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all instances of segments in the code

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and place a marker in the right margin

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and the reason for that is that it

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allows you to quickly see the code for

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each instance by hovering over the

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marker or to jump to any occurence by

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clicking on the marker now click into a

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blank line to clear the marker so I'll do

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that now and what I need to do for this

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error to come up because I copy and

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pasted but what I didn't do was add another

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or leave the original message their

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so going to type that again so you

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can see this problem

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alright so you can see what's happened

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now that I've made it extra long this is

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was the original error that i wanted to

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show you note that we no longer got

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a green tick in the box in the top

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right-hand corner and just to confirm

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if i come over and select segment

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again you can see there's other errors

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again and if I just click back

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we still got an error showing over there

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and I can hover over that line too long

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and 130 is greater than a 120

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characters and I clicked on the warning

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that you take me automatically to

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line to show where the problem is

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you can see it's got to line 28 and

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obviously it's pretty clear on the fact

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that that's underlined that that's where

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the problem is

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so the problem here is that the Python

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parser doesn't have a 120

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character restriction because if it did

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work our code will execute and we can run

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this its still going to actually work

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the code obviously still work so the

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problem is that isn't that the pyhon

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parcer can't handle something greater

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than 120 characters it's just that the

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python standards do recommend a maximum

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length which used to be 79 characters

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now the reason is largely down to

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readability especially when coding in

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a terminal window

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now google actually specify a maximum

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length of 80 characters with a few

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exceptions and let me bring the link up

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on the screen quickly so you can read

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more about that on that link that I just pasted

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in but to also if you want

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to have a full half argument google

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python line length and you can really

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become embroiled in much utility the

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time is much better spent coding than

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worrying about such details the bottom

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line here is not to be too concerned

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about whether it's 79 characters or its

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a 120 whether it's 80 but

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let's actually go back and appease

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IntelliJ so that we're not distracted by

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warnings in that right margin i'm just

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going to go back to intellij again

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we can actually fix it pretty easily we

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can place the cursor before the words

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separated here and press enter and you

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can see that

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intellij correctly fixes the problem for

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us because it's split the line and sort

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out the quotes for us automatically so

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that still valid Python syntax so you'll

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often see long lines especially text

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strings like this one spilled out of two

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or more lines in the code now keep in

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mind that python also has a line

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continuation character which is a

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backslash let's have a look at how that

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works

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we're going to actually cut that

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text I'm just going to undo that change

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but and undo which was a command z

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on a Mac and control z on a pc or

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linux machine i'm going to copy that

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entire input i'm going to actually put

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it into a variable so I'm going to just

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type...

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....

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...

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and unsurprisingly we're getting an

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error on that line as well indicating

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that the lines too long so we can

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split in the same way i can position the

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cursor just before separated and press

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enter that fixes the problem at least

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for the input prompt variable but note

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that this time because we've had in a

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string that fixed it by adding this

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backslash at the end of the first line

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so if you want to split a line you can

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use the you can use a backslash

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character just like intelliJ has done

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here and I can fix the next line

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now by changing that to input....

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just confirming that program

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still runs and still getting the outputs

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so still working

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so again if you want to split a line you

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can use that backslash character to do

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that just like intellij done here

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on line 28 unfortunately many style

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guides including Google's specify that

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you shouldn't use the line continuation

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character unless theirs no alternative

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so you may actually find strings like

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ours enclosed in parentheses instead to

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show you how that works i'm going to

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delete the parentheses like so we go

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back to the start of the line and add our

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left parentheses then go to the

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right of the line second line

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right parenthesis the other thing you

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00:09:47,250 --> 00:09:48,930
need to do is make sure that these are

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lined up correctly and once I've line them up

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00:09:51,540 --> 00:09:52,840
correctly you can see that warning

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00:09:52,840 --> 00:09:55,230
actually disappears but without doing

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that you'll get a weird error here about

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continuation line under indented

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for vision indent so just make sure

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thats the double quotes are

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00:10:03,600 --> 00:10:05,910
basically in line so I've mentioned this

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so that you can make sense of code

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written by other programmers a line can

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be broken using that backslash

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00:10:11,700 --> 00:10:13,740
continuation character but most

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expressions can also be split without

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a line continuation character if the

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expression is enclosed in parentheses as

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it is in the example now for the input

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_prompt variable on-screen

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some style guides such as Google suggest

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you use parentheses instead of the

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backslash whenever possible and that's

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why IntelliJ didn't insert the backslash

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when the string was included as an

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argument to the input function earlier

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on line 30 because it was enclosed in

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parentheses the backslash actually

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wasn't necessary

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alright so that's it that's the end of

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our challenge and I hope you've got a

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00:10:46,420 --> 00:10:47,880
lot out of it and let's move on to the

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next video