diff --git a/README.md b/README.md
index 59882a1..7d193ae 100644
--- a/README.md
+++ b/README.md
@@ -19,6 +19,12 @@ On a mac:
 stack test
 ```
 
+## Run a single test file
+
+```
+stack runghc -- -isrc -itest test/Cis194/Hw/SomeSpec.hs
+```
+
 ## Using QuickCheck in ghci
 
     :m +Test.QuickCheck
diff --git a/src/Cis194/Hw/LogAnalysis.hs b/src/Cis194/Hw/LogAnalysis.hs
index 3adfa15..c3512df 100644
--- a/src/Cis194/Hw/LogAnalysis.hs
+++ b/src/Cis194/Hw/LogAnalysis.hs
@@ -6,22 +6,46 @@ module Cis194.Hw.LogAnalysis where
 import  Cis194.Hw.Log
 
 parseMessage :: String -> LogMessage
-parseMessage s = Unknown s
+parseMessage s =
+  case words s of
+    "E":i:t:ws -> buildMessage (Error (read i)) t ws
+    "I":t:ws -> buildMessage Info t ws
+    "W":t:ws -> buildMessage Warning t ws
+    _ -> Unknown s
+
+buildMessage :: MessageType -> String -> [String] -> LogMessage
+buildMessage m t ws = LogMessage m (read t) (unwords ws)
 
 parse :: String -> [LogMessage]
-parse _ = []
+parse = map parseMessage . lines
 
 insert :: LogMessage -> MessageTree -> MessageTree
+insert Unknown{} t = t
+insert l Leaf = Node Leaf l Leaf
+insert n@(LogMessage _ nt _) (Node l m@(LogMessage _ mt _) r)
+  | nt < mt = Node (insert n l) m r
+  | nt > mt = Node l m (insert n r)
 insert _ t = t
 
 build :: [LogMessage] -> MessageTree
-build _ = Leaf
+build = foldl (flip insert) Leaf
 
 inOrder :: MessageTree -> [LogMessage]
-inOrder _ = []
+inOrder t = go t []
+  where
+    go (Node l m r) = go l . (m:) . go r
+    go Leaf = id
 
 -- whatWentWrong takes an unsorted list of LogMessages, and returns a list of the
 -- messages corresponding to any errors with a severity of 50 or greater,
 -- sorted by timestamp.
 whatWentWrong :: [LogMessage] -> [String]
-whatWentWrong _ = []
+whatWentWrong = map getString . filter isSevere . inOrder . build
+
+isSevere :: LogMessage -> Bool
+isSevere (LogMessage (Error s) _ _) = s >= 50
+isSevere _ = False
+
+getString :: LogMessage -> String
+getString (LogMessage _ _ s) = s
+getString (Unknown s) = s