13 lines
493 B
Plaintext
13 lines
493 B
Plaintext
main :: [sys_message]
|
|
main = [ Stdout (show n ++ ": " ++ toroman n ++ "\n")
|
|
| n <- [1990, 2008, 1666, 2023]]
|
|
|
|
toroman :: num->[char]
|
|
toroman 0 = ""
|
|
toroman n = d ++ toroman (n - v)
|
|
where digits = [("M",1000),("CM",900),("D",500),("CD",400),
|
|
("C",100),("XC",90),("L",50),("XL",40),
|
|
("X",10),("IX",9),("V",5),("IV",4),
|
|
("I",1)]
|
|
(d, v) = hd [(d,v) | (d,v) <- digits; v <= n]
|