Day 3:387

d3golf.hs

@@ -1,8 +1,13 @@
 import Data.List
-d=id
-v p@(x:s)=(length p,length x,p)
-q l z = fromEnum$l`div`2<z 
-c=foldr(\x y->2*y+x)0.reverse
-u w i=i*(2^w-1-i)
-t (h,w,i)=u w$c$map(q h.sum.map(subtract 48.fromEnum))$transpose i
-main=interact$show.((,).d<*>d).t.v.lines
+d=foldr(\x y->2*y+x)0.reverse
+v=(\i->i*(4095-i)).d.m
+c q=read.pure.head.q.sortBy((.length).compare.length).group.sort
+m=map(c head).transpose
+startsWith d=filter((==d).pure.head)
+mult f[[]]=[]
+mult f xs=do
+    let i=c f$head$transpose xs
+    let s=map tail$startsWith(show i)xs
+    i:mult f s
+t x=(d $ mult last x)*(d $ mult head x)
+main=interact$show.((,).t<*>v).lines