24 lines
551 B
Text
24 lines
551 B
Text
quickselect: function [a k][
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arr: new a
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while ø [
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indx: random 0 (size arr)-1
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pivot: arr\[indx]
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remove 'arr .index indx
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left: select arr 'item -> item<pivot
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right: select arr 'item -> item>pivot
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when.has: k [
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[= size left] -> return pivot
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[< size left] -> arr: new left
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true [
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k: (k - size left) - 1
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arr: new right
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]
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]
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]
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]
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v: [9 8 7 6 5 0 1 2 3 4]
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print map 0..(size v)-1 'i ->
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quickselect v i
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