Day 5

inputs/5.txt

@@ -0,0 +1,512 @@
+[Q] [J]                         [H]
+[G] [S] [Q]     [Z]             [P]
+[P] [F] [M]     [F]     [F]     [S]
+[R] [R] [P] [F] [V]     [D]     [L]
+[L] [W] [W] [D] [W] [S] [V]     [G]
+[C] [H] [H] [T] [D] [L] [M] [B] [B]
+[T] [Q] [B] [S] [L] [C] [B] [J] [N]
+[F] [N] [F] [V] [Q] [Z] [Z] [T] [Q]
+ 1   2   3   4   5   6   7   8   9 
+
+move 1 from 8 to 1
+move 1 from 6 to 1
+move 3 from 7 to 4
+move 3 from 2 to 9
+move 11 from 9 to 3
+move 1 from 6 to 9
+move 15 from 3 to 9
+move 5 from 2 to 3
+move 3 from 7 to 5
+move 6 from 9 to 3
+move 6 from 1 to 6
+move 2 from 3 to 7
+move 5 from 4 to 5
+move 7 from 9 to 4
+move 2 from 9 to 5
+move 10 from 4 to 2
+move 6 from 5 to 4
+move 2 from 7 to 6
+move 10 from 2 to 3
+move 21 from 3 to 5
+move 1 from 3 to 6
+move 3 from 6 to 9
+move 1 from 8 to 9
+move 5 from 4 to 5
+move 4 from 9 to 3
+move 17 from 5 to 1
+move 1 from 6 to 2
+move 16 from 5 to 1
+move 3 from 3 to 6
+move 6 from 6 to 4
+move 1 from 2 to 4
+move 4 from 1 to 2
+move 2 from 6 to 2
+move 28 from 1 to 3
+move 1 from 9 to 7
+move 1 from 8 to 7
+move 1 from 5 to 4
+move 1 from 2 to 6
+move 1 from 3 to 1
+move 3 from 2 to 5
+move 1 from 6 to 3
+move 4 from 4 to 7
+move 5 from 5 to 2
+move 1 from 5 to 6
+move 6 from 1 to 3
+move 1 from 6 to 2
+move 26 from 3 to 6
+move 2 from 7 to 9
+move 4 from 7 to 3
+move 19 from 6 to 3
+move 6 from 2 to 4
+move 5 from 3 to 2
+move 1 from 9 to 7
+move 26 from 3 to 8
+move 6 from 4 to 3
+move 1 from 3 to 8
+move 1 from 6 to 7
+move 6 from 3 to 6
+move 6 from 6 to 4
+move 1 from 9 to 2
+move 2 from 4 to 9
+move 22 from 8 to 2
+move 2 from 6 to 5
+move 1 from 9 to 1
+move 1 from 6 to 5
+move 1 from 7 to 5
+move 3 from 6 to 7
+move 2 from 6 to 1
+move 1 from 1 to 5
+move 3 from 5 to 9
+move 4 from 8 to 4
+move 2 from 1 to 4
+move 18 from 2 to 1
+move 2 from 7 to 8
+move 3 from 9 to 5
+move 8 from 1 to 9
+move 5 from 9 to 3
+move 1 from 9 to 8
+move 2 from 9 to 4
+move 2 from 7 to 8
+move 5 from 5 to 7
+move 1 from 9 to 3
+move 4 from 8 to 4
+move 1 from 7 to 8
+move 4 from 4 to 3
+move 2 from 8 to 3
+move 1 from 8 to 9
+move 2 from 1 to 8
+move 3 from 4 to 5
+move 1 from 8 to 4
+move 1 from 9 to 3
+move 1 from 8 to 5
+move 8 from 1 to 8
+move 11 from 2 to 9
+move 12 from 3 to 5
+move 1 from 3 to 9
+move 1 from 8 to 5
+move 11 from 9 to 3
+move 4 from 5 to 9
+move 3 from 8 to 7
+move 3 from 7 to 8
+move 1 from 5 to 8
+move 7 from 4 to 3
+move 1 from 4 to 5
+move 1 from 2 to 8
+move 3 from 7 to 6
+move 3 from 4 to 8
+move 1 from 7 to 9
+move 2 from 4 to 7
+move 5 from 8 to 1
+move 3 from 6 to 5
+move 2 from 4 to 2
+move 1 from 9 to 4
+move 1 from 8 to 6
+move 1 from 2 to 9
+move 1 from 8 to 5
+move 3 from 8 to 4
+move 3 from 4 to 2
+move 4 from 3 to 9
+move 17 from 5 to 9
+move 9 from 9 to 6
+move 1 from 9 to 3
+move 5 from 6 to 3
+move 3 from 6 to 3
+move 8 from 9 to 5
+move 2 from 8 to 5
+move 1 from 4 to 8
+move 1 from 5 to 3
+move 1 from 8 to 5
+move 3 from 2 to 6
+move 3 from 1 to 4
+move 7 from 5 to 1
+move 1 from 2 to 6
+move 13 from 3 to 6
+move 2 from 7 to 8
+move 13 from 6 to 5
+move 3 from 5 to 7
+move 6 from 5 to 6
+move 1 from 7 to 6
+move 2 from 7 to 3
+move 1 from 6 to 8
+move 13 from 3 to 5
+move 9 from 5 to 9
+move 7 from 5 to 7
+move 17 from 9 to 2
+move 3 from 4 to 7
+move 9 from 2 to 9
+move 10 from 9 to 3
+move 8 from 7 to 8
+move 2 from 5 to 3
+move 4 from 2 to 6
+move 11 from 3 to 9
+move 9 from 6 to 5
+move 5 from 9 to 8
+move 1 from 3 to 1
+move 3 from 9 to 1
+move 2 from 5 to 2
+move 1 from 7 to 9
+move 2 from 9 to 4
+move 2 from 9 to 8
+move 13 from 1 to 8
+move 3 from 8 to 5
+move 27 from 8 to 1
+move 10 from 5 to 9
+move 1 from 7 to 2
+move 2 from 4 to 3
+move 10 from 9 to 6
+move 1 from 8 to 7
+move 15 from 1 to 9
+move 13 from 9 to 5
+move 15 from 5 to 7
+move 5 from 1 to 3
+move 8 from 7 to 1
+move 7 from 7 to 1
+move 16 from 1 to 8
+move 4 from 3 to 9
+move 4 from 1 to 7
+move 4 from 9 to 6
+move 5 from 2 to 7
+move 15 from 8 to 6
+move 1 from 9 to 1
+move 3 from 3 to 4
+move 1 from 9 to 7
+move 1 from 2 to 7
+move 1 from 2 to 7
+move 1 from 8 to 1
+move 3 from 4 to 8
+move 3 from 8 to 1
+move 8 from 6 to 8
+move 7 from 1 to 4
+move 11 from 6 to 8
+move 14 from 6 to 5
+move 13 from 8 to 7
+move 4 from 7 to 5
+move 15 from 7 to 4
+move 6 from 5 to 4
+move 2 from 5 to 9
+move 1 from 5 to 2
+move 3 from 8 to 5
+move 19 from 4 to 7
+move 10 from 5 to 8
+move 2 from 6 to 8
+move 1 from 4 to 8
+move 2 from 7 to 9
+move 9 from 7 to 4
+move 6 from 4 to 6
+move 11 from 4 to 8
+move 2 from 5 to 4
+move 5 from 6 to 4
+move 1 from 6 to 7
+move 3 from 9 to 5
+move 3 from 8 to 5
+move 3 from 7 to 6
+move 11 from 8 to 7
+move 1 from 9 to 5
+move 1 from 6 to 8
+move 1 from 2 to 1
+move 5 from 4 to 9
+move 2 from 4 to 1
+move 2 from 1 to 4
+move 1 from 1 to 9
+move 4 from 5 to 1
+move 1 from 4 to 6
+move 17 from 7 to 5
+move 9 from 8 to 7
+move 6 from 9 to 7
+move 3 from 1 to 9
+move 12 from 7 to 9
+move 12 from 9 to 5
+move 5 from 7 to 9
+move 17 from 5 to 3
+move 7 from 3 to 1
+move 5 from 1 to 5
+move 5 from 9 to 2
+move 4 from 3 to 5
+move 1 from 4 to 8
+move 5 from 2 to 1
+move 22 from 5 to 9
+move 3 from 7 to 6
+move 6 from 6 to 9
+move 2 from 5 to 4
+move 1 from 6 to 3
+move 2 from 4 to 1
+move 3 from 8 to 2
+move 1 from 3 to 4
+move 24 from 9 to 1
+move 4 from 3 to 9
+move 2 from 2 to 9
+move 2 from 3 to 1
+move 1 from 8 to 6
+move 1 from 6 to 9
+move 1 from 8 to 9
+move 2 from 7 to 4
+move 1 from 8 to 3
+move 1 from 4 to 7
+move 3 from 9 to 8
+move 1 from 2 to 1
+move 9 from 9 to 3
+move 1 from 8 to 7
+move 1 from 4 to 3
+move 2 from 9 to 7
+move 1 from 9 to 3
+move 2 from 8 to 4
+move 12 from 3 to 8
+move 2 from 1 to 7
+move 1 from 4 to 3
+move 30 from 1 to 5
+move 6 from 5 to 7
+move 12 from 7 to 2
+move 1 from 3 to 4
+move 2 from 1 to 3
+move 1 from 4 to 9
+move 10 from 5 to 7
+move 10 from 2 to 6
+move 8 from 8 to 3
+move 3 from 1 to 3
+move 5 from 6 to 3
+move 2 from 8 to 5
+move 1 from 9 to 2
+move 2 from 8 to 6
+move 4 from 7 to 2
+move 3 from 2 to 7
+move 2 from 7 to 5
+move 1 from 4 to 9
+move 11 from 3 to 1
+move 7 from 6 to 9
+move 3 from 2 to 3
+move 10 from 1 to 7
+move 14 from 7 to 5
+move 3 from 7 to 6
+move 5 from 9 to 7
+move 29 from 5 to 7
+move 6 from 3 to 9
+move 2 from 9 to 7
+move 15 from 7 to 5
+move 11 from 5 to 6
+move 5 from 9 to 5
+move 10 from 5 to 8
+move 1 from 2 to 4
+move 1 from 8 to 2
+move 2 from 4 to 3
+move 2 from 5 to 9
+move 8 from 8 to 9
+move 11 from 9 to 3
+move 1 from 1 to 8
+move 18 from 7 to 3
+move 1 from 9 to 3
+move 28 from 3 to 5
+move 12 from 6 to 7
+move 1 from 2 to 9
+move 15 from 7 to 2
+move 1 from 8 to 1
+move 10 from 2 to 9
+move 10 from 5 to 3
+move 2 from 2 to 3
+move 18 from 3 to 4
+move 6 from 9 to 4
+move 1 from 1 to 7
+move 1 from 6 to 4
+move 1 from 8 to 2
+move 1 from 9 to 4
+move 2 from 9 to 4
+move 19 from 4 to 3
+move 1 from 7 to 9
+move 1 from 9 to 7
+move 1 from 6 to 8
+move 3 from 2 to 8
+move 2 from 9 to 5
+move 15 from 3 to 1
+move 7 from 5 to 1
+move 3 from 4 to 9
+move 1 from 7 to 2
+move 3 from 3 to 1
+move 6 from 5 to 2
+move 3 from 3 to 9
+move 4 from 9 to 2
+move 5 from 5 to 3
+move 1 from 3 to 5
+move 3 from 5 to 7
+move 3 from 8 to 5
+move 1 from 7 to 5
+move 4 from 5 to 1
+move 4 from 4 to 2
+move 2 from 7 to 8
+move 12 from 1 to 6
+move 1 from 8 to 6
+move 6 from 2 to 3
+move 9 from 3 to 8
+move 1 from 3 to 4
+move 3 from 6 to 1
+move 2 from 9 to 2
+move 1 from 4 to 5
+move 2 from 8 to 3
+move 10 from 2 to 1
+move 2 from 4 to 7
+move 12 from 1 to 4
+move 1 from 5 to 1
+move 7 from 4 to 9
+move 2 from 3 to 2
+move 6 from 9 to 2
+move 1 from 9 to 1
+move 1 from 7 to 8
+move 5 from 6 to 7
+move 3 from 6 to 1
+move 6 from 2 to 3
+move 2 from 4 to 3
+move 1 from 6 to 8
+move 1 from 6 to 7
+move 8 from 3 to 9
+move 2 from 4 to 5
+move 3 from 2 to 4
+move 10 from 8 to 2
+move 22 from 1 to 9
+move 9 from 2 to 4
+move 1 from 1 to 3
+move 1 from 3 to 2
+move 3 from 2 to 4
+move 2 from 7 to 1
+move 14 from 4 to 2
+move 2 from 1 to 8
+move 2 from 4 to 5
+move 4 from 7 to 8
+move 24 from 9 to 6
+move 3 from 5 to 9
+move 1 from 9 to 8
+move 1 from 5 to 2
+move 1 from 6 to 7
+move 6 from 9 to 1
+move 1 from 7 to 3
+move 5 from 8 to 6
+move 9 from 6 to 3
+move 4 from 1 to 4
+move 2 from 1 to 2
+move 11 from 6 to 3
+move 13 from 3 to 2
+move 2 from 9 to 8
+move 8 from 3 to 8
+move 2 from 8 to 5
+move 1 from 7 to 5
+move 3 from 6 to 3
+move 11 from 8 to 5
+move 13 from 2 to 4
+move 10 from 5 to 2
+move 2 from 3 to 4
+move 2 from 5 to 7
+move 15 from 4 to 9
+move 2 from 7 to 4
+move 2 from 4 to 2
+move 2 from 4 to 9
+move 2 from 4 to 2
+move 1 from 3 to 8
+move 1 from 8 to 1
+move 1 from 1 to 2
+move 1 from 6 to 3
+move 7 from 2 to 4
+move 1 from 5 to 3
+move 7 from 9 to 1
+move 7 from 1 to 2
+move 4 from 6 to 9
+move 12 from 9 to 7
+move 6 from 7 to 5
+move 1 from 3 to 5
+move 7 from 4 to 7
+move 3 from 7 to 8
+move 3 from 8 to 6
+move 18 from 2 to 9
+move 7 from 2 to 3
+move 15 from 9 to 4
+move 3 from 3 to 9
+move 1 from 3 to 1
+move 3 from 5 to 4
+move 1 from 1 to 2
+move 1 from 9 to 2
+move 2 from 6 to 2
+move 5 from 7 to 6
+move 5 from 2 to 7
+move 3 from 3 to 4
+move 5 from 5 to 3
+move 6 from 7 to 4
+move 9 from 4 to 2
+move 18 from 4 to 9
+move 6 from 2 to 1
+move 1 from 1 to 9
+move 4 from 7 to 4
+move 7 from 2 to 4
+move 1 from 2 to 8
+move 1 from 4 to 2
+move 4 from 3 to 4
+move 16 from 9 to 5
+move 9 from 9 to 8
+move 1 from 9 to 7
+move 4 from 1 to 2
+move 2 from 5 to 4
+move 10 from 5 to 4
+move 4 from 2 to 1
+move 5 from 1 to 2
+move 1 from 8 to 5
+move 1 from 6 to 5
+move 4 from 8 to 5
+move 2 from 6 to 9
+move 3 from 6 to 2
+move 2 from 9 to 1
+move 1 from 7 to 6
+move 1 from 3 to 8
+move 9 from 5 to 9
+move 4 from 8 to 1
+move 2 from 8 to 2
+move 1 from 5 to 7
+move 9 from 9 to 8
+move 1 from 7 to 5
+move 9 from 8 to 2
+move 6 from 1 to 6
+move 6 from 2 to 6
+move 10 from 2 to 5
+move 5 from 2 to 1
+move 1 from 3 to 5
+move 8 from 5 to 4
+move 5 from 1 to 3
+move 10 from 6 to 8
+move 3 from 6 to 9
+move 4 from 3 to 1
+move 5 from 8 to 2
+move 4 from 5 to 9
+move 1 from 3 to 7
+move 1 from 7 to 3
+move 1 from 8 to 6
+move 1 from 6 to 1
+move 15 from 4 to 8
+move 5 from 9 to 2
+move 1 from 9 to 1
+move 1 from 1 to 3
+move 6 from 4 to 8
+move 12 from 8 to 7
+move 1 from 3 to 5
+move 3 from 1 to 9
+move 13 from 4 to 9
+move 5 from 7 to 2
+move 1 from 5 to 4
+move 8 from 9 to 5
+move 6 from 2 to 5
+move 2 from 5 to 6
+

inputs/5_test.txt

@@ -0,0 +1,9 @@
+    [D]    
+[N] [C]    
+[Z] [M] [P]
+ 1   2   3 
+
+move 1 from 2 to 1
+move 3 from 1 to 3
+move 2 from 2 to 1
+move 1 from 1 to 2

ocaml/5.ml

@@ -0,0 +1,97 @@
+#load "str.cma" ;;
+#use "lib/utils.ml" ;;
+
+type crane_model = CrateMover9000 | CrateMover9001 ;;
+
+type move = {cnt: int; from: int; into: int} ;;
+
+let parse_stacks txt =
+  let lines = String.split_on_char '\n' txt in
+  let charw = 4 in
+  let nstacks = ((String.length (List.nth lines 0)) + 1) / charw in
+  let lines = List.rev lines
+  |> List.tl in
+  let parse_line line =
+    List.init nstacks (fun i -> i + 1)
+    |> List.map (fun i -> (String.get line ((i - 1) * charw + 1)))
+  in
+  List.map parse_line lines
+  |> transpose
+  |> List.map (List.filter (fun c -> c <> ' '))
+in
+
+let parse_moves txt =
+  let lines = String.split_on_char '\n' txt
+  |> List.filter (fun l -> String.trim l <> "")
+  in
+  let parse_line line =
+    let tokens = String.split_on_char ' ' line in
+    { cnt = int_of_string (List.nth tokens 1);
+      from = int_of_string (List.nth tokens 3) - 1;
+      into = int_of_string (List.nth tokens 5) - 1;
+    }
+  in
+  List.map parse_line lines
+in
+
+let format_stacks stacks =
+  stacks |> List.mapi (fun i stack ->
+    let boxes = List.map (fun c -> Printf.sprintf "[%c]" c) stack in
+    let tokens = (string_of_int (i + 1)) :: boxes in
+    String.concat " " tokens
+  ) |> String.concat "\n"
+in
+
+let debug_move stacks move =
+  Printf.printf "move %d from %d to %d\n" move.cnt (move.from+1) (move.into+1);
+  print_endline (format_stacks stacks)
+in
+
+let solution_of stacks =
+  let last_char stack =
+    let len = List.length stack in
+    let c = List.nth stack (len - 1) in
+    Printf.sprintf "%c" c
+  in
+  String.concat "" (List.map last_char stacks)
+in
+
+let move_boxes stacks moves crane =
+  moves |> List.fold_left (fun stacks move ->
+    let new_stack = List.nth stacks (move.from)
+    |> List.rev
+    |> List.to_seq
+    in
+    let buf = Seq.take move.cnt new_stack
+    |> List.of_seq
+    in
+    let buf = match crane with
+    | CrateMover9000 -> buf
+    | CrateMover9001 -> List.rev buf
+    in
+    let new_stack = Seq.drop move.cnt new_stack
+    |> List.of_seq
+    |> List.rev
+    in
+    let stacks = stacks |> List.mapi (fun i stack ->
+      if i = move.from then new_stack
+      else if i = move.into then stack @ buf
+      else stack
+    ) in
+    (* let _ = debug_move stacks move in *)
+    stacks
+  ) stacks
+in
+
+(* Silence warnings *)
+let _ = debug_move in
+
+let contents = read_file "inputs/5.txt" in
+let parts = Str.split (Str.regexp "\n\n") contents in
+let stacks = parse_stacks (List.nth parts 0) in
+let moves = parse_moves (List.nth parts 1) in
+(* let _ = print_endline (format_stacks stacks) in *)
+let res1 = move_boxes stacks moves CrateMover9000 in
+let res2 = move_boxes stacks moves CrateMover9001 in
+Printf.printf "Solution 1: %s\n" (solution_of res1);
+Printf.printf "Solution 2: %s\n" (solution_of res2)

ocaml/lib/utils.ml

@@ -3,6 +3,14 @@ let read_file filename =
   let s = really_input_string ch (in_channel_length ch) in
   close_in ch;
   s
-  ;;
+;;
 
-let list_of_chars str = List.init (String.length str) (String.get str)
+let list_of_chars str =
+  List.init (String.length str) (String.get str)
+;;
+
+let rec transpose = function
+  | []
+  | [] :: _ -> []
+  | rows -> List.map List.hd rows :: transpose (List.map List.tl rows)
+;;