CGAL 5.4 - Manual
Convex_hull_2/vector_convex_hull_2.cpp
#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/convex_hull_2.h>
#include <vector>
typedef K::Point_2 Point_2;
typedef std::vector<Point_2> Points;
int main()
{
Points points, result;
points.push_back(Point_2(0,0));
points.push_back(Point_2(10,0));
points.push_back(Point_2(10,10));
points.push_back(Point_2(6,5));
points.push_back(Point_2(4,1));
CGAL::convex_hull_2( points.begin(), points.end(), std::back_inserter(result) );
std::cout << result.size() << " points on the convex hull" << std::endl;
return 0;
}