day 5 part 1 done

src/Javran/AdventOfCode/Y2023/Day5.hs

@@ -46,8 +46,29 @@ almanacP = do
     many entryP
   pure (seeds, rs)
 
+mkMapper :: AlmanacMap -> Int -> Int
+mkMapper xs = auxLookup
+  where
+    -- key: src, value: (dst, range)
+    m :: IM.IntMap (Int, Int)
+    m = IM.fromList do
+      (dst, src, rng) <- xs
+      pure (src, (dst, rng))
+
+    -- rely on split and maxView on left result to do our work
+    auxLookup i
+      | Just (dst, _) <- cur = dst
+      | Just ((src, (dst, rng)), _) <- IM.maxViewWithKey lm
+      , i < src + rng =
+          dst + (i - src)
+      | otherwise = i
+      where
+        (lm, cur, _) = IM.splitLookup i m
+
 instance Solution Day5 where
   solutionSolved _ = False
   solutionRun _ SolutionContext {getInputS, answerShow} = do
-    xs <- consumeOrDie almanacP <$> getInputS
-    print xs
+    (seeds, maps) <- consumeOrDie almanacP <$> getInputS
+    let fs = fmap mkMapper maps
+        locs = foldl' (\xs f -> fmap f xs) seeds fs
+    answerShow (minimum locs)