Compile time sort

template <int N>
struct PrintNumber;

template <int... Items>
struct IndexSequence {
};

template <typename Sequence1, typename Sequence2>
struct ConcatSequence;

template<int... I1, int... I2>
struct ConcatSequence<IndexSequence<I1...>, IndexSequence<I2...>> {
    using type = IndexSequence<I1..., I2...>;
};

template <typename Sequence, int... Items>
struct T;

template <typename Sequence, int Max, int First, int... Others>
struct T<Sequence, Max, First, Others...> {
    using OtherSequence = typename ConcatSequence<Sequence, IndexSequence<(Max < First ? Max : First)>>::type;
    using U = T<OtherSequence, (Max < First ? First : Max), Others...>;
    U u;
};

template <typename Sequence, int Max>
struct T<Sequence, Max>;

template <int... Items, int Max>
struct T<IndexSequence<Items...>, Max> {
    using U = int;
    using Next = T<IndexSequence<>, Items...>;
    Next next;
    PrintNumber<Max> _;
};

template <int Max>
struct T<IndexSequence<>, Max> {
    using U = int;
    PrintNumber<Max> _;
};

int main() {
    static_assert(false, "Sort [2, 1, 7, 4, 9, 6, 8, 5, 3] at compile time:");
    T<IndexSequence<>, 2, 1, 7, 4, 9, 6, 8, 5, 3>::U test;
}