yuzhiy.cpp

#include <cstdio>
#include <vector>
inline void dbg(const char* msg)
{
    std::puts(msg);
    std::fflush(stdout);
}
// template<typename T,typename ...Args>
// struct helper{using type=T;};
// template<typename ...Targs>
// using helper_t=typename helper<Targs...>::type;
//这应该算思考过程吧就不删了

template<typename...Args>
auto make_vector(Args&&...args)->decltype(auto){
 return std::vector({std::forward<Args>(args)...});
}
struct X {
    X() noexcept
    {
        dbg("X()");
    };
    ~X() noexcept
    {
        dbg("~X()");
    };
    X(const X&)
    {
        dbg("X(const X&)");
    }
    X(X&&) noexcept
    {
        dbg("X(X&&)");
    }
};
void test()
{
    static_assert(requires {
        {
            make_vector(std::vector{1, 2, 3})
        } -> std::same_as<std::vector<std::vector<int>>>;
        {
            make_vector(1, 2, 3)
        } -> std::same_as<std::vector<int>>;
        make_vector(1, 2, 3).size() == 3;
    });
    X    x1;
    X    x2;
    auto vec = make_vector(x1, std::move(x2));
}
int main()
{
    test();
    dbg("test end");
}