ranges-v3 benchmark

rngs.cpp

int64_t compute(int64_t sz, size_t iter_num)
{
    using namespace ranges::v3;
    auto res = view::generate([sz]{
        auto xs = view::iota(0LL, sz);
        auto ys = view::zip_with([](auto x, auto y){ return x+y; },
                                 xs, xs | view::drop(1));
        return accumulate(ys | view::stride(100), 0LL);
    });
    return *(res | view::drop_exactly(iter_num-1)).begin();
}