#include <iostream>
{
    cout << "string_literal<3>=" << s << endl;
    
    auto ab = a + b;
    cout << "a=" << a << endl;
    cout << "b=" << b << endl;
    cout << "a+b=" << ab << endl;
    static_assert(ab.size() == 6, "***");
    cout << "(a+b).size()=" << ab.size() << endl;
    cout << "(a+b)[0]=" << ab[0] << endl;
    cout << "(a+b)[5]=" << ab[5] << endl;
}
#include <iostream>
{
    cout << "42 as string=" << n42 << endl;
    cout << "9999 as string=" << n9999 << endl;
}
{
    try
    {
        return 0;
    }
    catch (const std::exception& e)
    {
        std::cerr << "MRPT error: " << e.what() << std::endl;
        return -1;
    }
}