nsuke

#ifndef common_tuple_hash_h
#define common_tuple_hash_h
#include <tuple>
namespace std{
  namespace
  {
    template <class t>
    inline void hash_combine(std::size_t& seed, t const& v)
    {
      seed ^= hash<t>()(v) + 0x9e3779b9 + (seed<<6) + (seed>>2);