#include <exception> // for std::exception
#include <iostream>
#include <stdexcept> // for std::runtime_error
#include <string>

class ArrayException : public std::runtime_error
{
public:
    ArrayException(const std::string &error)
        : std::runtime_error{error}
    {
    }
    const char *what() const noexcept override // 如果无需要可以不重写
    {
        return "数组类专用异常";
    }
};
class IntArray
{
private:
    int m_data[10]{}; // assume array is length 3 for simplicity
public:
    int &operator[](int index)
    {
        if (index < 0 || index >= 10)
            throw ArrayException("下标越界");
        return m_data[index];
    }
};
int main()
{
    try
    {
        IntArray array{};
        array[10] = 5;
    }
    catch (const ArrayException &exception)
    {
        // 根据需要增加其它额外的处理语句
        std::cerr << exception.what() << "\n";
    }
    catch (const std::exception &exception)
    {
        std::cerr << exception.what() << "\n";
    }
}