12/one.icl

   1 module one
   2
   3 import StdEnv
   4 import Data.Func
   5 import Data.Tuple
   6
   7 read :: *File -> [(Char, Int)]
   8 read f
   9         # (l, f) = freadline f
  10         | l.[size l - 1] <> '\n' = []
  11         = [(l.[0], toInt (l % (1, size l - 2))):read f]
  12
  13 Start w
  14         # (io, w) = stdio w
  15         # ls = read io
  16         = (\s->abs s.x+abs s.y) $ foldl move {x=0,y=0,dirs=dirs} ls
  17
  18 dirs = [(1, 0),(0,-1),(-1,0),(0,1):dirs]
  19
  20 :: Ship = {x :: Int, y :: Int, dirs :: [(Int, Int)]}
  21
  22 move s ('N', n) = {s & y=s.y+n}
  23 move s ('S', n) = {s & y=s.y-n}
  24 move s ('E', n) = {s & x=s.x+n}
  25 move s ('W', n) = {s & x=s.x-n}
  26 move s=:{dirs=[(dx, dy):_]} ('F', n) = {s & x=s.x+dx*n, y=s.y+dy*n}
  27 move s ('R', n) = {s & dirs=drop (n/90) s.dirs}
  28 move s ('L', n) = {s & dirs=drop (3*(n/90)) s.dirs}