diff --git a/13.rkt b/13.rkt
index ab1671e..076c1cc 100644
--- a/13.rkt
+++ b/13.rkt
@@ -27,16 +27,14 @@
        [x x])]))
 
 (define (part1 input)
-  (for/sum ([pair (in-list input)]
-            [idx (in-naturals 1)]
+  (for/sum ([pair (in-list input)] [idx (in-naturals 1)]
             #:when (= -1 (cmp (first pair) (second pair))))
     idx))
 
 (define (part2 input)
-  (define all-packets (list* '((2)) '((6)) (apply append input)))
-  (define sorted (sort all-packets #{= -1 (cmp %1 %2)}))
-  (* (add1 (index-of sorted '((2))))
-     (add1 (index-of sorted '((6))))))
+  (define special '(((2)) ((6))))
+  (define sorted (sort (apply append special input) #{= -1 (cmp %1 %2)}))
+  (~>> special (map #{index-of sorted %}) (map add1) (apply *)))
 
 (define (parse fname)
   (define (parse-line line)