38 lines
813 B
Factor
38 lines
813 B
Factor
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! Copyright (C) 2014 John Benediktsson
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! See http://factorcode.org/license.txt for BSD license
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USING: combinators kernel locals math math.order sequences
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sequences.private ;
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IN: sorting.quick
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<PRIVATE
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:: (quicksort) ( seq from to -- )
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from to < [
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from to + 2/ :> p
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from :> l!
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to :> r!
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p seq nth-unsafe :> p-nth
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[ l r <= ] [
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[ l seq nth-unsafe p-nth before? ] [ l 1 + l! ] while
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[ r seq nth-unsafe p-nth after? ] [ r 1 - r! ] while
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l r <= [
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l r seq exchange-unsafe
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l 1 + l!
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r 1 - r!
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] when
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] while
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seq from r (quicksort)
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seq l to (quicksort)
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] when ; inline recursive
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PRIVATE>
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: quicksort ( seq -- )
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0 over length 1 - (quicksort) ;
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