main :: [sys_message]
main = [Stdout (lay [word ++ ": " ++ show (canmakeword blocks word) | word <- tests])]

tests :: [[char]]
tests = ["A","BARK","BOOK","TREAT","common","SqUaD","cOnFuSe"]

canmakeword :: [[char]]->[char]->bool
canmakeword []     word   = False
canmakeword blocks []     = True
canmakeword blocks (a:as) = #match ~= 0 & canmakeword rest as
                            where match = [b | b<-blocks; ucase a $in b]
                                  rest  = hd match $del blocks

del :: *->[*]->[*]
del item []     = []
del item (a:as) = a:del item as, if a ~= item
                = as,            otherwise

in :: *->[*]->bool
in item []     = False
in item (a:as) = a = item \/ item $in as

ucase :: char->char
ucase ch = ch,            if n<code 'a' \/ n>code 'z'
         = decode (n-32), otherwise
           where n = code ch

blocks :: [[char]]
blocks = ["BO","XK","DQ","CP","NA","GT","RE","TG","QD","FS",
          "JW","HU","VI","AN","OB","ER","FS","LY","PC","ZM"]