Submission #1112588

---

Source Code Expand

type token = Int of int | BinOp of char
type exp = EInt of int | EBinOp of char * exp * exp

let array_of_string s =
  Array.init (String.length s) (fun i -> s.[i])

let string_of_array a =
  String.init (Array.length a) (fun i -> a.(i))

let denote_rpn int binop tokens =
  List.hd
    (List.fold_left (fun stack token ->
      match stack, token with
      | _, Int n -> int n :: stack
      | n :: m :: stack, BinOp op -> binop op n m :: stack) [] tokens)

let rec to_queued_rpn = function
  | [] -> []
  | es ->
      to_queued_rpn (List.concat (List.map (function
        | EInt n -> []
        | EBinOp (_, e1, e2) -> [e1; e2]) es))
      @ List.map (function
        | EInt n -> Int n
        | EBinOp (op, _, _) -> BinOp op) es
let to_queued_rpn e = to_queued_rpn [e]

let () =
  read_line ()
  |> array_of_string
  |> Array.to_list
  |> List.map (function
      | ('0' | '1' | '2' | '3' | '4' | '5' | '6' | '7' | '8' | '9') as c -> Int (int_of_char c - int_of_char '0')
      | ('+' | '-' | '*') as c -> BinOp c)
  |> denote_rpn (fun n -> EInt n) (fun op e1 e2 -> EBinOp (op, e1, e2))
  |> to_queued_rpn
  |> List.map (function
      | Int n -> char_of_int (n + int_of_char '0')
      | BinOp c -> c)
  |> Array.of_list
  |> string_of_array
  |> print_endline

Submission Info

Compile Error

File "./Main.ml", line 13, characters 6-125:
Warning 8: this pattern-matching is not exhaustive.
Here is an example of a value that is not matched:
([], BinOp _)
File "./Main.ml", line 32, characters 14-182:
Warning 8: this pattern-matching is not exhaustive.
Here is an example of a value that is not matched:
'a'

Judge Result