Question

我一直在Ocaml中键入一个代码，该类存储象棋棋盘位置（棋子，颜色，位置）的数组。我需要编写一种方法以8x8字符串格式将其打印出来。我的代码给出错误，我该怎么做？

我实际上已经考虑过制作一个数组矩阵并将值放入其中，但是我不知道如何按位置匹配每个片段，所以我想出了一个模式，用于匹配字符串的各个片段，但是我不认为这是最好的解决方案。到目前为止，我编写了以下代码：

type chess_letter = A | B | C | D | E | F | G | H
and chess_piece = King | Queen | Rook | Bishop | Knight | Pawn
and chess_colour = Black | White 
and chess_position = Alive of chess_letter * int | Dead


class chess = 
object (self)
val number_of_players = 2
val first_player = White
val board = Array.make_matrix 8 8 None  
val pieces_on_board = [|(Rook, Black, Alive (A,8)); (Knight, Black, Alive (B,8)); (Bishop, Black, Alive (C,8)); (Queen, Black, Alive (D,8)); 
                                    (King, Black, Alive (E,8)); (Bishop, Black, Alive (F,8)); (Knight, Black, Alive (G,8)); (Rook, Black, Alive (H,8)); 
                                (Pawn, Black, Alive (A,7)); (Pawn, Black, Alive (B,7));   (Pawn, Black, Alive (C,7));   (Pawn, Black, Alive (D,7)); 
                                                          (Pawn, Black, Alive (E,7)); (Pawn, Black, Alive (F,7));   (Pawn, Black, Alive (G,7));   (Pawn, Black, Alive (H,7));
                                (Pawn, White, Alive (A,2)); (Pawn, White, Alive (B,2));   (Pawn, White, Alive (C,2));   (Pawn, White, Alive ( D,2));
                                                            (Pawn, White, Alive (E,2)); (Pawn, White, Alive (F,2));   (Pawn, White, Alive (G,2));   (Pawn, White, Alive (H,2));
                                                            (Rook, White, Alive (A,1)); (Knight, White, Alive (B,1)); (Bishop, White, Alive (C,1)); (Queen, White, Alive  (D,1)); 
                                    (King, White, Alive (E,1)); (Bishop, White, Alive (F,1)); (Knight, White, Alive (G,1)); (Rook, White, Alive (H,1))|] 

        method put_pieces_on_board pieces_on_board = match pieces_on_board with
                | (Rook, White, Alive (chess_letter, int)) -> "R"   | (Knight, White, Alive (chess_letter, int)) -> "N" 
                | (Bishop, White, Alive (chess_letter, int)) -> "B" | (Queen, White, Alive (chess_letter, int)) -> "Q" 
                | (King, White, Alive (chess_letter, int)) -> "K"   | (Pawn, White, Alive (chess_letter, int)) -> "P"
                | (Rook, Black, Alive (chess_letter, int)) -> "r"   | (Knight, Black, Alive (chess_letter, int)) -> "n" 
                | (Bishop, Black, Alive (chess_letter, int)) -> "b" | (Queen, Black, Alive (chess_letter, int)) -> "q"  
                | (King, Black, Alive (chess_letter, int)) -> "k"   | (Pawn, Black, Alive (chess_letter, int)) -> "p"
                | (Rook, White, Dead) -> "."                        | (Knight, White, Dead) -> "." 
                | (Bishop, White, Dead) -> "."                      | (Queen, White, Dead) -> "." 
                | (King, White, Dead) -> "."                        | (Pawn, White, Dead) -> "."
                | (Rook, Black, Dead) -> "."                        | (Knight, Black, Dead) -> "." 
                | (Bishop, Black, Dead) -> "."                      | (Queen, Black, Dead) -> "."  
                | (King, Black, Dead) -> "."                        | (Pawn, Black, Dead) -> "."

    method print = print_string(string_of_string self#put_pieces_on_board ^ "---" )
    end;;

非常感谢您提前回答。

Answer 1

当我尝试编译您的代码时，我抱怨没有定义string_of_string。但这很可能不是您要问的错误。

您想遍历数组并为每个元素调用self#put_pieces_on_board。

执行此操作的一个函数是Array.map，它将为您提供字符串数组。您可以使用Array.to_list将其转换为列表，然后使用String.concat获得一个大字符串。但是，仍然需要做一些工作才能制作出漂亮的8x8网格。

method print =
    Array.map self#put_pieces_on_board pieces_on_board |>
    Array.to_list |>
    String.concat " "

我不确定这是否是您要的内容，但也许会有所帮助。

在Ocaml中，哪种方法最适合将数组打印为字符串？

1 个答案: