6

User will input the string, list or tuples.

I have to extract the first do and the last two values. For the first two values:

ls[:2]

For the last two values how can I do it?

If n is the total number of values the last two item can be sliced as:

[n-1:]

How can I put down in the code?

razlebe
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Joyfulgrind
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3 Answers3

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ls[-2:]

Negative numbers in slices are simply evaluated by adding len(ls), so this is the same as ls[len(ls) - 2:]. For more information on slices, refer to the Python tutorial or this excellent stackoverflow answer.

Community
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phihag
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2
ls[-2:]

would be the way to do it, as negative indexes count from the end.

glglgl
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1

if you have a list like this: a_list = [1,2,3] you can get last two [2,3] elements by a_list[-2:]

juankysmith
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