Day 06 - cleanup 2

day06/default.nix

@@ -3,41 +3,20 @@
 with lib;
 
 let
-  input = stringToCharacters (fileContents ./input.txt);
-
-  foldl'' = f: l: let
-    initial = take 2 l;
-    base = f (elemAt initial 0) (elemAt initial 1);
-  in foldl f base (drop 2 l);
-
-  zipLists = ls: let 
-    minLength = foldl'' min (map length ls);
-
-    f = n: pipe ls [
-      (map (l: elemAt l n))
-      (imap0 (i: nameValuePair (toString i)))
-      listToAttrs
-    ];
-  in genList f minLength;
-
-  zipNSelfDrop1 = n: l: 
-    zipLists (map (i: drop i l) (range 0 (n - 1)));
-
-  countUntil = pred: l: let
-    innerCount = list: count:
-      if pred (head list)
+  countWithNUntil = n: pred: list: let
+    inner = list': count:
+      if pred (take n list')
         then count
-        else innerCount (tail list) (count + 1);
-  in innerCount l 0;
+        else inner (tail list') (count + 1);
+  in inner list 0;
 
   allItemsAreUnique = l: l == []
-                      || (!(elem (head l) (tail l))
-                         && allItemsAreUnique (tail l));
+    || !(elem (head l) (tail l)) && allItemsAreUnique (tail l);
 
-  answerN = n: pipe input [
-    (zipNSelfDrop1 n)
-    (map attrValues)
-    (countUntil allItemsAreUnique)
+  answerN = n: pipe ./input.txt [
+    fileContents
+    stringToCharacters
+    (countWithNUntil n allItemsAreUnique)
     (add n)
     toString
   ];