You are given a list of points on a coordinate plane. We need you find the convex hull formed by these points. The convex hull of a set X of points in the Euclidean plane is the smallest convex set that contains X. For instance: when X is a bounded subset of the plane, the convex hull may be visualized as the shape formed by a rubber band stretched around X. If a point lies on edge, it's included.

The points are presented as a list of coordinates [x, y] in which x and y are integers. The result returns as a sequence of indexes of points in the given list; points lie on the convex hull in clockwise order (see the picture). The sequence starts from the bottom...