diff --git a/bin/d5/dune b/bin/d5/dune
new file mode 100644
index 0000000..b758f1a
--- /dev/null
+++ b/bin/d5/dune
@@ -0,0 +1,4 @@
+(executable
+ (public_name d5)
+ (name main)
+ (libraries utils))
diff --git a/bin/d5/input.txt b/bin/d5/input.txt
new file mode 100644
index 0000000..6e96408
--- /dev/null
+++ b/bin/d5/input.txt
@@ -0,0 +1,512 @@
+    [M]             [Z]     [V]
+    [Z]     [P]     [L]     [Z] [J]
+[S] [D]     [W]     [W]     [H] [Q]
+[P] [V] [N] [D]     [P]     [C] [V]
+[H] [B] [J] [V] [B] [M]     [N] [P]
+[V] [F] [L] [Z] [C] [S] [P] [S] [G]
+[F] [J] [M] [G] [R] [R] [H] [R] [L]
+[G] [G] [G] [N] [V] [V] [T] [Q] [F]
+ 1   2   3   4   5   6   7   8   9
+
+move 6 from 9 to 3
+move 2 from 2 to 1
+move 1 from 8 to 2
+move 3 from 7 to 2
+move 7 from 6 to 9
+move 1 from 9 to 5
+move 3 from 5 to 7
+move 6 from 8 to 6
+move 1 from 7 to 8
+move 6 from 6 to 5
+move 4 from 5 to 8
+move 9 from 2 to 9
+move 1 from 2 to 3
+move 3 from 1 to 3
+move 3 from 5 to 1
+move 10 from 3 to 5
+move 4 from 4 to 6
+move 2 from 7 to 6
+move 2 from 6 to 9
+move 6 from 8 to 6
+move 1 from 4 to 3
+move 1 from 4 to 5
+move 1 from 4 to 1
+move 2 from 3 to 1
+move 1 from 3 to 7
+move 8 from 1 to 9
+move 1 from 1 to 2
+move 1 from 2 to 7
+move 6 from 6 to 3
+move 7 from 3 to 5
+move 14 from 5 to 6
+move 2 from 1 to 3
+move 5 from 5 to 8
+move 5 from 8 to 1
+move 2 from 7 to 1
+move 5 from 6 to 9
+move 8 from 9 to 3
+move 13 from 9 to 3
+move 7 from 1 to 4
+move 6 from 4 to 1
+move 22 from 3 to 1
+move 1 from 9 to 3
+move 2 from 6 to 1
+move 1 from 3 to 4
+move 7 from 9 to 8
+move 2 from 1 to 7
+move 2 from 3 to 2
+move 2 from 6 to 9
+move 2 from 7 to 8
+move 1 from 3 to 6
+move 9 from 8 to 6
+move 1 from 2 to 4
+move 8 from 1 to 2
+move 1 from 9 to 4
+move 3 from 4 to 1
+move 1 from 4 to 6
+move 10 from 6 to 5
+move 5 from 2 to 9
+move 6 from 9 to 3
+move 2 from 5 to 3
+move 2 from 9 to 7
+move 7 from 5 to 8
+move 5 from 6 to 2
+move 3 from 3 to 7
+move 3 from 3 to 5
+move 4 from 5 to 8
+move 1 from 3 to 5
+move 6 from 6 to 8
+move 1 from 5 to 7
+move 9 from 8 to 9
+move 1 from 3 to 1
+move 7 from 2 to 7
+move 9 from 7 to 6
+move 2 from 2 to 3
+move 7 from 9 to 3
+move 9 from 6 to 8
+move 7 from 3 to 4
+move 2 from 7 to 6
+move 4 from 4 to 5
+move 3 from 5 to 6
+move 2 from 7 to 4
+move 5 from 4 to 7
+move 13 from 8 to 4
+move 2 from 9 to 4
+move 2 from 8 to 7
+move 6 from 7 to 5
+move 6 from 4 to 2
+move 1 from 7 to 5
+move 3 from 2 to 7
+move 1 from 7 to 8
+move 3 from 2 to 4
+move 2 from 3 to 9
+move 2 from 7 to 2
+move 6 from 5 to 4
+move 3 from 6 to 2
+move 2 from 6 to 9
+move 5 from 2 to 9
+move 12 from 4 to 8
+move 3 from 9 to 2
+move 12 from 1 to 5
+move 4 from 4 to 6
+move 12 from 8 to 9
+move 2 from 6 to 5
+move 1 from 4 to 8
+move 1 from 4 to 1
+move 3 from 2 to 1
+move 2 from 6 to 7
+move 1 from 5 to 9
+move 2 from 1 to 4
+move 10 from 5 to 1
+move 2 from 7 to 3
+move 18 from 9 to 7
+move 8 from 7 to 2
+move 1 from 9 to 6
+move 1 from 6 to 7
+move 10 from 7 to 9
+move 1 from 4 to 2
+move 19 from 1 to 5
+move 8 from 5 to 9
+move 3 from 8 to 4
+move 2 from 5 to 2
+move 2 from 3 to 6
+move 10 from 5 to 2
+move 4 from 1 to 2
+move 2 from 9 to 2
+move 1 from 1 to 6
+move 2 from 5 to 6
+move 1 from 8 to 7
+move 1 from 5 to 8
+move 1 from 5 to 6
+move 18 from 2 to 5
+move 5 from 2 to 1
+move 6 from 5 to 8
+move 1 from 8 to 9
+move 2 from 2 to 4
+move 1 from 2 to 6
+move 2 from 7 to 6
+move 1 from 4 to 1
+move 4 from 8 to 5
+move 1 from 2 to 9
+move 2 from 8 to 3
+move 1 from 3 to 6
+move 1 from 4 to 8
+move 1 from 8 to 9
+move 10 from 5 to 7
+move 5 from 5 to 1
+move 2 from 4 to 1
+move 3 from 7 to 6
+move 12 from 1 to 4
+move 8 from 9 to 5
+move 6 from 7 to 4
+move 1 from 7 to 9
+move 4 from 4 to 3
+move 1 from 1 to 7
+move 3 from 9 to 5
+move 2 from 3 to 1
+move 1 from 7 to 6
+move 8 from 4 to 7
+move 1 from 7 to 6
+move 7 from 6 to 4
+move 2 from 1 to 3
+move 1 from 7 to 1
+move 1 from 3 to 7
+move 1 from 1 to 6
+move 4 from 9 to 3
+move 5 from 4 to 6
+move 12 from 6 to 2
+move 3 from 9 to 4
+move 8 from 2 to 6
+move 2 from 9 to 6
+move 8 from 5 to 6
+move 4 from 5 to 8
+move 14 from 6 to 3
+move 11 from 4 to 9
+move 2 from 2 to 7
+move 8 from 3 to 9
+move 11 from 3 to 6
+move 14 from 9 to 1
+move 7 from 1 to 3
+move 2 from 9 to 5
+move 2 from 2 to 8
+move 6 from 7 to 5
+move 1 from 9 to 8
+move 13 from 6 to 3
+move 4 from 6 to 8
+move 3 from 1 to 6
+move 5 from 5 to 8
+move 7 from 8 to 7
+move 2 from 1 to 8
+move 1 from 4 to 1
+move 4 from 8 to 9
+move 8 from 7 to 5
+move 1 from 8 to 1
+move 4 from 9 to 3
+move 1 from 4 to 5
+move 5 from 5 to 2
+move 1 from 8 to 9
+move 1 from 8 to 6
+move 2 from 6 to 2
+move 4 from 8 to 6
+move 4 from 1 to 8
+move 4 from 8 to 5
+move 1 from 9 to 8
+move 1 from 2 to 3
+move 4 from 6 to 1
+move 1 from 8 to 2
+move 3 from 5 to 4
+move 4 from 2 to 5
+move 1 from 7 to 9
+move 1 from 2 to 6
+move 3 from 1 to 8
+move 2 from 4 to 5
+move 2 from 6 to 1
+move 3 from 8 to 9
+move 4 from 9 to 2
+move 1 from 7 to 1
+move 1 from 6 to 7
+move 4 from 1 to 6
+move 1 from 7 to 4
+move 6 from 2 to 8
+move 2 from 4 to 8
+move 1 from 9 to 5
+move 3 from 6 to 2
+move 1 from 6 to 4
+move 7 from 3 to 5
+move 2 from 8 to 1
+move 3 from 2 to 8
+move 6 from 8 to 5
+move 17 from 5 to 3
+move 2 from 1 to 6
+move 3 from 8 to 3
+move 1 from 9 to 5
+move 11 from 5 to 2
+move 40 from 3 to 5
+move 11 from 2 to 7
+move 4 from 7 to 8
+move 1 from 8 to 9
+move 1 from 3 to 5
+move 1 from 4 to 8
+move 19 from 5 to 8
+move 7 from 7 to 8
+move 16 from 5 to 2
+move 6 from 5 to 8
+move 1 from 5 to 8
+move 1 from 9 to 4
+move 1 from 6 to 1
+move 1 from 4 to 7
+move 1 from 6 to 9
+move 1 from 1 to 7
+move 1 from 7 to 3
+move 1 from 7 to 2
+move 1 from 9 to 8
+move 1 from 3 to 4
+move 1 from 4 to 6
+move 14 from 2 to 9
+move 24 from 8 to 4
+move 8 from 8 to 3
+move 1 from 6 to 3
+move 16 from 4 to 1
+move 3 from 8 to 4
+move 3 from 3 to 8
+move 4 from 3 to 4
+move 1 from 3 to 9
+move 13 from 9 to 4
+move 16 from 1 to 8
+move 8 from 8 to 1
+move 3 from 1 to 7
+move 1 from 8 to 6
+move 1 from 3 to 8
+move 10 from 8 to 5
+move 5 from 5 to 2
+move 3 from 8 to 9
+move 1 from 8 to 9
+move 1 from 4 to 5
+move 5 from 2 to 6
+move 3 from 5 to 2
+move 1 from 6 to 1
+move 5 from 1 to 5
+move 1 from 1 to 5
+move 2 from 7 to 3
+move 2 from 3 to 2
+move 1 from 5 to 7
+move 7 from 5 to 3
+move 5 from 9 to 5
+move 2 from 7 to 9
+move 4 from 5 to 6
+move 2 from 9 to 8
+move 2 from 2 to 4
+move 5 from 3 to 5
+move 1 from 3 to 2
+move 7 from 4 to 9
+move 1 from 8 to 1
+move 1 from 2 to 1
+move 9 from 4 to 6
+move 2 from 1 to 8
+move 1 from 3 to 9
+move 2 from 8 to 6
+move 13 from 4 to 6
+move 1 from 8 to 7
+move 2 from 9 to 6
+move 3 from 5 to 7
+move 3 from 2 to 5
+move 3 from 2 to 6
+move 5 from 6 to 2
+move 4 from 2 to 5
+move 4 from 5 to 7
+move 5 from 5 to 7
+move 7 from 9 to 6
+move 6 from 7 to 2
+move 22 from 6 to 5
+move 10 from 5 to 8
+move 7 from 5 to 4
+move 8 from 8 to 5
+move 18 from 6 to 2
+move 5 from 7 to 5
+move 1 from 8 to 2
+move 6 from 5 to 1
+move 7 from 4 to 2
+move 4 from 1 to 5
+move 1 from 7 to 9
+move 1 from 8 to 6
+move 1 from 7 to 8
+move 10 from 5 to 9
+move 12 from 2 to 1
+move 8 from 5 to 2
+move 19 from 2 to 9
+move 1 from 6 to 8
+move 13 from 9 to 3
+move 8 from 1 to 2
+move 5 from 1 to 3
+move 10 from 2 to 1
+move 7 from 2 to 5
+move 3 from 5 to 7
+move 4 from 1 to 3
+move 1 from 2 to 3
+move 3 from 1 to 2
+move 1 from 8 to 6
+move 2 from 7 to 5
+move 4 from 1 to 3
+move 6 from 5 to 4
+move 2 from 2 to 1
+move 1 from 2 to 9
+move 6 from 4 to 5
+move 5 from 5 to 9
+move 1 from 6 to 8
+move 1 from 5 to 1
+move 6 from 9 to 2
+move 5 from 2 to 4
+move 3 from 1 to 6
+move 2 from 4 to 7
+move 22 from 3 to 9
+move 1 from 8 to 4
+move 2 from 4 to 3
+move 2 from 6 to 1
+move 2 from 1 to 5
+move 1 from 6 to 7
+move 1 from 7 to 4
+move 6 from 3 to 7
+move 1 from 2 to 4
+move 8 from 7 to 3
+move 1 from 4 to 5
+move 1 from 7 to 9
+move 5 from 3 to 6
+move 1 from 8 to 4
+move 4 from 3 to 2
+move 32 from 9 to 3
+move 3 from 6 to 7
+move 5 from 9 to 3
+move 1 from 9 to 7
+move 2 from 9 to 2
+move 2 from 4 to 3
+move 2 from 5 to 4
+move 5 from 3 to 2
+move 3 from 7 to 8
+move 1 from 7 to 2
+move 1 from 8 to 5
+move 1 from 3 to 4
+move 5 from 4 to 5
+move 4 from 5 to 2
+move 3 from 5 to 7
+move 1 from 7 to 5
+move 1 from 6 to 5
+move 2 from 8 to 5
+move 15 from 2 to 4
+move 3 from 5 to 6
+move 4 from 6 to 5
+move 2 from 5 to 2
+move 1 from 2 to 4
+move 25 from 3 to 9
+move 2 from 5 to 2
+move 11 from 9 to 2
+move 13 from 2 to 1
+move 4 from 4 to 7
+move 12 from 9 to 8
+move 6 from 7 to 8
+move 7 from 4 to 7
+move 7 from 7 to 8
+move 1 from 5 to 1
+move 5 from 4 to 3
+move 2 from 2 to 1
+move 2 from 9 to 5
+move 7 from 1 to 7
+move 1 from 1 to 4
+move 12 from 3 to 2
+move 1 from 3 to 9
+move 1 from 1 to 3
+move 1 from 9 to 1
+move 7 from 7 to 2
+move 1 from 4 to 7
+move 2 from 8 to 7
+move 7 from 1 to 2
+move 1 from 3 to 4
+move 26 from 2 to 1
+move 4 from 8 to 1
+move 3 from 1 to 6
+move 1 from 6 to 3
+move 1 from 6 to 9
+move 1 from 3 to 8
+move 20 from 1 to 3
+move 1 from 9 to 7
+move 4 from 7 to 1
+move 1 from 5 to 3
+move 4 from 3 to 5
+move 1 from 6 to 2
+move 6 from 3 to 2
+move 8 from 1 to 4
+move 1 from 1 to 5
+move 3 from 1 to 4
+move 7 from 2 to 4
+move 10 from 3 to 8
+move 4 from 4 to 3
+move 12 from 4 to 7
+move 3 from 3 to 1
+move 2 from 4 to 3
+move 2 from 8 to 1
+move 6 from 8 to 9
+move 5 from 9 to 6
+move 1 from 9 to 3
+move 3 from 8 to 7
+move 10 from 8 to 5
+move 4 from 8 to 7
+move 9 from 7 to 9
+move 4 from 8 to 4
+move 2 from 4 to 3
+move 3 from 1 to 7
+move 11 from 7 to 4
+move 6 from 4 to 8
+move 1 from 7 to 3
+move 4 from 5 to 1
+move 5 from 3 to 6
+move 5 from 9 to 4
+move 1 from 9 to 8
+move 10 from 4 to 8
+move 5 from 1 to 2
+move 1 from 7 to 6
+move 9 from 6 to 3
+move 7 from 8 to 7
+move 3 from 4 to 1
+move 2 from 2 to 1
+move 9 from 8 to 3
+move 10 from 5 to 8
+move 18 from 3 to 9
+move 1 from 7 to 8
+move 1 from 5 to 3
+move 4 from 8 to 3
+move 2 from 6 to 3
+move 6 from 7 to 2
+move 1 from 5 to 3
+move 1 from 1 to 9
+move 10 from 3 to 9
+move 4 from 1 to 8
+move 13 from 8 to 1
+move 3 from 1 to 8
+move 3 from 2 to 4
+move 5 from 2 to 6
+move 5 from 6 to 4
+move 28 from 9 to 2
+move 2 from 9 to 5
+move 2 from 5 to 2
+move 1 from 3 to 7
+move 2 from 1 to 4
+move 3 from 8 to 3
+move 1 from 9 to 4
+move 3 from 4 to 6
+move 2 from 3 to 7
+move 8 from 1 to 5
+move 3 from 7 to 6
+move 14 from 2 to 8
+move 1 from 9 to 1
+move 6 from 5 to 6
+move 4 from 2 to 5
+move 9 from 8 to 2
+move 4 from 8 to 4
+move 7 from 2 to 4
+move 12 from 4 to 3
+move 5 from 4 to 7
+move 5 from 7 to 4
+move 1 from 8 to 7
+move 1 from 4 to 5
+move 2 from 5 to 4
+move 1 from 5 to 8
+move 1 from 5 to 9
diff --git a/bin/d5/main.ml b/bin/d5/main.ml
new file mode 100644
index 0000000..d484d7c
--- /dev/null
+++ b/bin/d5/main.ml
@@ -0,0 +1,53 @@
+open Utils
+
+let initial_state =
+    let ht = Hashtbl.create 12345                                     in
+    let _ = Hashtbl.add ht 1 ["S"; "P"; "H"; "V"; "F"; "G"]           in
+    let _ = Hashtbl.add ht 2 ["M"; "Z"; "D"; "V"; "B"; "F"; "J"; "G"] in
+    let _ = Hashtbl.add ht 3 ["N"; "J"; "L"; "M"; "G"]                in
+    let _ = Hashtbl.add ht 4 ["P"; "W"; "D"; "V"; "Z"; "G"; "N"]      in
+    let _ = Hashtbl.add ht 5 ["B"; "C"; "R"; "V"]                     in
+    let _ = Hashtbl.add ht 6 ["Z"; "L"; "W"; "P"; "M"; "S"; "R"; "V"] in
+    let _ = Hashtbl.add ht 7 ["P"; "H"; "T"]                          in
+    let _ = Hashtbl.add ht 8 ["V"; "Z"; "H"; "C"; "N"; "S"; "R"; "Q"] in
+    let _ = Hashtbl.add ht 9 ["J"; "Q"; "V"; "P"; "G"; "L"; "F"]      in
+    ht
+
+exception InvalidMoveLine
+
+let parse_move line =
+    match String.split_on_char ' ' line with
+        | "move" :: count :: "from" :: st_from :: "to" :: st_to :: [] ->
+                (int_of_string count, int_of_string st_from, int_of_string st_to)
+        | _ -> raise InvalidMoveLine
+
+let move stacks f (count, idx_from, idx_to) =
+    let from_stack = Hashtbl.find stacks idx_from in
+    let to_stack = Hashtbl.find stacks idx_to in
+    let rec aux count res_from append_to =
+        if count = 0 then (res_from, append_to)
+        else match res_from with
+        | h :: t -> aux (count - 1) t (h :: append_to)
+        | [] -> (res_from, append_to) in
+    let (res_from, res_to) = aux count from_stack [] in
+    let _ = Hashtbl.replace stacks idx_from res_from in
+    let _ = Hashtbl.replace stacks idx_to (List.append (f res_to) to_stack) in
+    stacks ;;
+
+let parsed_moves = read_file "bin/d5/input.txt"
+    |> List.filter_map
+        (fun line ->
+            try Some(parse_move line)
+            with InvalidMoveLine -> let _ = print_endline ("invalid line " ^ line) in None) ;;
+
+let solve f input =
+    let state = Hashtbl.copy initial_state in
+    let _ = input
+        |> List.map (move state f) in
+    let res = Hashtbl.length state
+        |> range
+        |> List.fold_left (fun acc x -> acc ^ (List.hd (Hashtbl.find state x))) "" in
+    print_endline ("\n" ^ res) ;;
+
+solve id parsed_moves ;;
+solve List.rev parsed_moves ;;