Function NextIterInCycle

libs/base/stl_helpers.hpp:376–381

template <typename Iter>
Iter NextIterInCycle(Iter it, Iter beg, Iter end)
{
  if (++it == end)
    return beg;
  return it;
}

template <typename Iter>
Iter PrevIterInCycle(Iter it, Iter beg, Iter end)