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23 lines
401 B
Elm
23 lines
401 B
Elm
module Triangle exposing (rows)
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import List
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nextRow : List Int -> List Int
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nextRow row =
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List.map2 (+) (0 :: row) (row ++ [ 0 ])
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rows : Int -> List (List Int)
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rows n =
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let
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loop i row =
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if i == n then
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[]
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else
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row :: loop (i + 1) (nextRow row)
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in
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if n < 0 then
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[]
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else
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loop 0 [ 1 ]
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