Graham Scan Algorithm

Graham's scan is a method for finding the convex hull of a finite set of points in the plane, the smallest convex polygon containing every point. It first sorts the points by angle from the lowest point, then walks around them in that order using a stack to detect and discard any point that would create a concavity in the boundary, leaving only the vertices of the hull in order around its perimeter. It is named after Ronald Graham, who published the original algorithm in 1972. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/