The function ch_melkman computes the counterclockwise sequence of extreme points of a sequence of points that forms a simple polyline or polygon.
generates the counterclockwise sequence of extreme points
of the points in the range [first, beyond).
The resulting sequence is placed starting at
position result, and the past-the-end iterator for
the resulting sequence is returned.
The default traits class Default_traits is the kernel in which the type InputIterator::value_type is defined.
It uses an implementation of Melkman's algorithm [Mel87]. Running time of this is linear.