２次元配列問題 クラス化

board.cpp

struct Pos {
    int x, y;
    Pos (int _x, int _y) {
        x = _x; y = _y;
    }
    bool operator==(const Pos &other) const {
        return x == other.x && y == other.y;
    }
};

struct Board {
private:
    char _board[Y * X];
public:
    char operator[](Pos pos) const {
        return _board[pos.y * X + pos.x];
    }
    
    char &operator[](Pos pos) {
        return _board[pos.y * X + pos.x];
    }
};