Created
April 29, 2019 15:34
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Roman Numbers in Scala
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def roman(n: Int) = { | |
def div(v: Int, d: Int) : (Int, Int) = (v / d, v % d) | |
val romanMap = List( | |
(1000, "M"), | |
(900, "CM"), | |
(500, "D"), | |
(400, "CD"), | |
(100, "C"), | |
(90, "XC"), | |
(50, "L"), | |
(40, "XL"), | |
(10, "X"), | |
(9, "IX"), | |
(5, "V"), | |
(4, "IV"), | |
(1, "I") | |
) | |
val (_, res) = romanMap.foldLeft((n, ""))((acc, elt) => { | |
val (diviser, letter) = elt | |
val (rest, tempResult) = acc | |
val (q, r) = div(rest, diviser) | |
(r, tempResult + letter * q) | |
}) | |
res | |
} | |
roman(3) | |
roman(4) | |
roman(9) | |
roman(12) | |
roman(69) | |
roman(22) | |
roman(16) | |
roman(2569) |
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