Evaluation the runtime of merge sort.
https://teamtreehouse.com/library/evaluating-the-runtime-of-merge-sort

in Python a recursive and an iterative version.

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In the recursive one we use list slicing with every recursion call, but we achieve

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the same end result using an iterative approach without using list slicing.

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Over there we declared two variables to keep track of the starting, and

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ending positions in the list.

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We could rewrite merge sort to do the same, but

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I'll leave that as an exercise for you.

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If you want some hints, or

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if you want any direction I've included a link in the notes with an implementation.

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So that is time complexity.

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Now just so we know, before moving on, for

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Python here our overall run time is not what I've listed here.