stable_partition

template <class InIt, class Pred>
InIt stable_partition(InIt Begin, InIt end, Pred p) {
    using val = std::iterator_traits<InIt>::value_type;
    std::vector<val> failed;

    InIt dest = Begin;

    for (InIt src = Begin; src != end; ++src)
        if (p(*src))
            * dest++ = std::move(*src);
        else
            failed.push_back(std::move(*src));
    auto ret = dest;
    for (auto const& f : failed)
        * dest++ = f;
    return ret;
}