STL set custom sort

Question

I was trying to resort a set when i realised that it was impossible to resort a set and i had to create a new set and have a custom sort function to resort it . I researched onl

Answer 1

In set the second parameter p2d_sortby_y does not name a type.

struct point_odered_by_y
{
    bool operator()(const Point2D& ptd1, const Point2D& ptd2) const
    {
        /* .. */
    }
};



typedef std::set pointset;
pointset s(begin(p2d_set), end(p2d_set));