8/one.icl

   1 module one
   2
   3 import StdEnv
   4
   5 read :: *File -> [Instr]
   6 read f
   7         # (l, f) = freadline f
   8         | l.[size l - 1] <> '\n' = []
   9         = [toInstr [c\\c<-:l | c <> '\n']:read f]
  10 where
  11         toInstr ['nop ':rs] = Nop (toInt (toString rs))
  12         toInstr ['acc ':rs] = Acc (toInt (toString rs))
  13         toInstr ['jmp ':rs] = Jmp (toInt (toString rs))
  14
  15 :: Instr = Nop Int | Acc Int | Jmp Int
  16
  17 Start w
  18         # (io, w) = stdio w
  19         # instr = read io
  20         # instr = {c\\c<-instr}
  21         = (one instr, two instr)
  22
  23 one = fst o interpret
  24 two = hd o filter snd o map interpret o nopjump 0
  25
  26 nopjump :: Int {Instr} -> [{Instr}]
  27 nopjump pc is
  28         | pc == size is = []
  29         = case is.[pc] of
  30                 Nop i = [update {i\\i<-:is} pc (Jmp i):nopjump (pc+1) is]
  31                 Jmp i = [update {i\\i<-:is} pc (Nop i):nopjump (pc+1) is]
  32                 _ = nopjump (pc+1) is
  33
  34 interpret :: {Instr} -> (Int, Bool)
  35 interpret instr = int [] 0 0
  36 where
  37         int vis pc acc
  38                 | pc >= size instr = (acc, True)
  39                 | isMember pc vis = (acc, False)
  40                 = case instr.[pc] of
  41                         Nop _ = int [pc:vis] (1 + pc) acc
  42                         Acc i = int [pc:vis] (1 + pc) (i + acc)
  43                         Jmp i = int [pc:vis] (i + pc) acc