libscatter/include/scatter/scatter.h

#include <stdint.h>
#ifdef COMPILE_TIME
    #include "9float.hpp"
    using scatter_key_t = ninefloat::Q<uint64_t,64>;
    static const scatter_key_t scatter_key_increment = ninefloat::Q<uint64_t,64>::min_increment();
#else
    using scatter_key_t = uint64_t;
    static const scatter_key_t scatter_key_increment = 1;
#endif

#include <vector>

namespace StorageTree{

    namespace _impl{

        template<class childs>
        struct subdivision
        {
            uint64_t weight;
            std::vector<childs> content;
            scatter_key_t begin;
            scatter_key_t end;
            static const bool divisible = true;
        };

        struct daemon_impl{
            uint64_t weight;
            scatter_key_t begin;
            scatter_key_t end;
            static const bool divisible = false;
        };
        
        template<class T>
        constexpr T max(T any = 0)
        {
            if(any>any+scatter_key_increment)
                return any
            return max(any+scatter_key_increment);
        }
    }


    using daemon        = _impl::daemon_impl;
    using server        = _impl::subdivision<daemon>;
    using subrack       = _impl::subdivision<server>;
    using rack          = _impl::subdivision<subrack>;
    using room          = _impl::subdivision<rack>;
    using datacenter    = _impl::subdivision<room>;
    using root          = _impl::subdivision<datacenter>;

    template<class T, std::enable_if_t<T::divisible>>
    void update_weights(T& root, uint64_t sub_ratio=1, scatter_key_t begin=0, scatter_key_t end=_impl::max<scatter_key_t>())
    {
        scatter_key_t address_space = end-begin;
        scatter_key_t base = begin
        for(int idx=0:idx<root.content.size();idx++)
        {
            auto& elem = root.content[idx];
            if(idx!=root.content.size()-1)
            {
                update_weights(elem, root.content.size()*sub_ratio, base, base+address_space/root.content.size());
                base = base+address_space/root.content.size()+scatter_key_increment;
            }
            else
                update_weights(elem, root.content.size()*sub_ratio, base, end);
            
        }
    }
    
    template<class T, std::enable_if_t<!T::divisible>>
    void update_weights(T& root, scatter_key_t begin, scatter_key_t end)
    { 
        this->begin = begin;
        this->end = end;
    }
}