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Contining with our strings2 program, I'm
going to delete everything except the

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definition of parrot on line 3,
and also the first slice.

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00:00:15,320 --> 00:00:17,760
The start, stop and step values in a slice

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can also be negative. So let's add some code on line 7,

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print then left parentheses parrot
left square bracket -4:2

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right square bracket then right
parenthesis. Now if we run this we'll find

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that this actually doesn't print out
anything. So it doesn't print the two

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characters starting 4 in from the end
of the string, and it's printing nothing, as

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I mentioned, and that's because you can't
go backwards from the starting position.

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So instead we'd have to write that as
-4, which we've got, but then -2,

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and as a comment that should give us Bl.

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As another example print

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parentheses parrot again, then left square
bracket -4:12 right square

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bracket right parenthesis, then that will
actually give us the same thing. So if we

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run this, you can see we've got Bl in both
cases there. So the first one, on line 7,

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that prints from index -4 and
that's B, capital B, up to but not

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including the second-to-last character
in the string, which is u.

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Now the second example, on line 8, prints the same
thing but this time it's interpreted as

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from index -4, up to but not
including index position 12.

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00:01:40,760 --> 00:01:43,860
So spend some time experimenting with negative indices.

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There's nothing tricky about them.
they're just counting from the end of

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the string, instead of from the beginning.
Make sure you can reproduce all the

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slices from the last video, using
negative indices. I'll do the one on line 5

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just to get you started,
and we'll do that just immediately under

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line 5. So the negative version of that
would be print parentheses parrot square

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bracket -14:-8. Then we want
our right to square bracket right

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parenthesis and that should give us the same result.

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So let's just run that to make sure that it
works, and you can see we've got Norweg

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00:02:21,970 --> 00:02:26,650
outputted twice. So again, make sure
you go through and reproduce all the

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slices from the last video, using
negative indices, to really make sure

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that you understand how they work. But
also, with that said, create your own

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strings and practice on them as well.

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In the next video, we'll see how to use a step in our slices.

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See you in the next video.