FLOLAC 2018 Week 1 (2018-5-03 16:20) -- Histogram

histogram.hs

--  FLOLAC 2018 Week 2 -- Histogram

histogram :: [Int] -> String

histogram ix =
       concat [ row n | n <- [heigh, heigh - 1  .. 1]] ++
       "==========\n"  ++
       "0123456789\n"
    where 
       row m = [ if mm < m then ' ' else '*' | mm <- accl ] ++ "\n" 
       accl = [ length $ filter (== nn ) ix | nn <- [0 .. 9] ]   
       heigh = maximum accl

-- In GHCi we should put the histogram output in 'putSrtLn' function 
-- In order to make "\n" actually be line feed
{-  e.g.
putStrLn (histogram [])

putStrLn (histogram [1,2,3,4,5,6,7])

putStrLn (histogram [1,6,4,2,7,8,4,9,3,0,3,9,7,3])

putStrLn (histogram [1,4,5,4,6,6,3,4,2,4,9])
-}