Merge branch 'master' of git.martlubbers.net:aoc20

[aoc20.git] / 8 / one.icl

diff --git a/8/one.icl b/8/one.icl
index 6b4fde3..4365516 100644 (file)
--- a/8/one.icl
+++ b/8/one.icl
@@ -21,22 +21,20 @@ Start w
        = (one instr, two instr)
 
 one = fst o interpret
-two = hd o filter snd o map interpret o nopjump 0
-
-nopjump :: Int {Instr} -> [{Instr}]
-nopjump pc is
-       | pc == size is = []
-       = case is.[pc] of
-               Nop i = [update {i\\i<-:is} pc (Jmp i):nopjump (pc+1) is]
-               Jmp i = [update {i\\i<-:is} pc (Nop i):nopjump (pc+1) is]
-               _ = nopjump (pc+1) is
+two is = [ acc \\i<-:is & pc<-[0..]
+       , let (acc, t) = interpret (update {i\\i<-:is} pc (swapnop i))
+       | t]
+where
+       swapnop (Nop i) = Jmp i
+       swapnop (Jmp i) = Nop i
+       swapnop i = i
 
 interpret :: {Instr} -> (Int, Bool)
 interpret instr = int [] 0 0
 where
        int vis pc acc
-               | pc >= size instr = (acc, True)
-               | isMember pc vis = (acc, False)
+               | pc >= size instr = (acc, True) // terminated
+               | isMember pc vis = (acc, False) // inf loop
                = case instr.[pc] of
                        Nop _ = int [pc:vis] (1 + pc) acc
                        Acc i = int [pc:vis] (1 + pc) (i + acc)