main :: IO () main = do { content <- readFile "in.txt" ; let -- change this following type annotation -- to change different type of the dictionary -- dict :: DM.Map S.ByteString Int -- dict :: IM.IntMap Int dict :: Trie Int dict = fromList (map parse_a_line (lines content)) .. where parse_a_line :: String -> (Key,Int) parse_a_line line = case words line of [key,val] -> (key,read val) _ -> error " parse error. "
Maps tend to be strict in their keys, but not in their values. You might be storing a lot of thunks with unparsed Strings instead of plain Int values. Something like this might make a difference wrt memory usage: [key,val] -> ((,) key) $! (read val) Hth, Claus
Here is a comparison of memory usage
Map : 345 MB IntMap : 146 MB Trie : 282 MB Python : 94 MB