Day 8: 520

d8golf.hs

@@ -0,0 +1,22 @@
+import Data.List
+q"012345"=pure 0
+q"12"=pure 1
+q"01346"=pure 2
+q"01236"=pure 3
+q"1256"=pure 4
+q"02356"=pure 5
+q"023456"=pure 6
+q"012"=pure 7
+q"0123456"=pure 8
+q"012356"=pure 9
+q _=Nothing
+t r=head[p|p<-permutations['a'..'g'],Nothing`notElem`map(p%)r]
+p%a=q.sort$foldr r a$zip['0'..]p
+r(n,o)=foldr(\h a->last(h:[ n|h==o]):a)[]
+v(p,n)=map((t p)%)n
+f[]=0
+f((Just x):y)=x+10*f y
+a=length.filter(`elem`(map pure[1,4,7,8])).concat
+b=sum.map(f.reverse)
+main=interact$show.((,).b<*>a).map d.lines
+d=v.fmap tail.splitAt 10.words