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import Control.Monad (forM_)
data Player = Player { name :: String
, rank :: Int
, matchLimit :: Int
} deriving (Show, Eq)
players :: [Player]
players = [ Player "orbekk" (-1) 4
, Player "ltsang" (-4) 4
, Player "sebh" 2 4
, Player "fringd" (-1) 4
, Player "sheyrax" (-2) 2
]
remove :: Eq a => a -> [a] -> [a]
remove p = filter (/=p)
matchPlayers :: [Player] -> [Player] -> ([Player], [(Player, Player)])
matchPlayers [] qs = (qs, [])
matchPlayers ps [] = (ps, [])
matchPlayers (p:ps) (q:qs)
| p == q = matchPlayers (p:ps) qs
| otherwise = ([p', q'] ++ s', (p, q) : m')
where p' = p { matchLimit = matchLimit p - 1 }
q' = q { matchLimit = matchLimit q - 1 }
(s', m') = matchPlayers (remove q ps) (remove p qs)
main = do
let (players', matches) = matchPlayers players players
print players'
forM_ matches $ \(p, q) ->
putStrLn ((name p) ++ " vs. " ++ (name q))
|
