one line

diff --git a/10/one.icl b/10/one.icl
index 32ffe8b..a71ff6d 100644 (file)
--- a/10/one.icl
+++ b/10/one.icl
@@ -16,10 +16,6 @@ Start w
        # ls = sort [0:read io]
        = (one ls, two ls)
 
-one ls = uncurry (*) $ foldl jolt (0, 1) [b-a\\a<-ls & b<-tl ls]
-where
-       jolt (j1, j3) 3 = (j1, j3+1)
-       jolt (j1, j3) 1 = (j1+1, j3)
-       jolt (j1, j3) _ = (j1, j3)
+one ls = prod $ map length $ group $ sort [3:[b-a\\a<-ls & b<-tl ls]]
 
 two ls = prod [[0,1,2,4,7,12,20,33,53]!!length l\\l<-group [b-a\\a<-ls & b<-tl ls] | all ((==)1) l]