ConvexHull

The convex hull (of a set Q of points) is the smallest convex polygon P for which each point in Q is either on the boundary of P or in its interior.We implicitly assume that all points in the set Q are unique and that Q contains at least three points which are not colinear.
Jarvis’s march
Jarvis’s march computes the convex hull of a set Q of points by a technique known as package wrapping (or gift wrapping). The algorithm runs in time O(nh), where h is the number of vertices of our polygon.
Okey.Let's enjoy it!