8 lines
179 B
OCaml
8 lines
179 B
OCaml
(* range operator *)
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let rec (--) a b =
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if a > b then
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[]
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else
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a :: (a+1) -- b
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let perf n = n = List.fold_left (+) 0 (List.filter (fun i -> n mod i = 0) (1 -- (n-1)))
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