23 lines
384 B
Text
23 lines
384 B
Text
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let rec fence s = function
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[] ->
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if s >= 3 then
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[[]]
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else
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[]
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| x :: xs ->
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if s mod 2 = 0 then
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List.map
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(fun ys -> x :: ys)
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(fence (s + 1) xs)
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@
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fence s xs
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else
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List.map
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(fun ys -> x :: ys)
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(fence s xs)
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@
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fence (s + 1) xs
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let ncsubseq = fence 0
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