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python - Iterate through a string forwards and backwards, extracting alternating characters

I'm studying python and there's a lab I can't seem to crack. We have a line e.g. shacnidw, that has to be transformed to sandwich. I somehow need to iterate with a for loop and pick the letters with odd indexes first, followed by backward even indexes. Like pick a letter with index 1,3,5,7,8,6,4,2.

It looks pretty obvious to use a list or slices, but we aren't allowed to use these functions yet. I guess the question is just how do I do it?


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Programming is all about decomposing complex problems into simpler ones. Try breaking it down into smaller steps.

  1. First, can you generate the numbers 1,3,5,7 in a for loop?
  2. Next, can you generate 8,6,4,2 in a second loop?

Tackling those two steps ought to get you on the right track.


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