Graham$$s algorithm for finding a convex hull$)$ Section $22\mathrm{.}10\mathrm{.}2$

introduced Graham$$s algorithm for finding a convex hull for a set of points.

Assume that the Java$$s coordinate system is used for the points. Implement the

algorithm using the following method: $/**$ Return the points that form a convex hull $*/$

public static ArrayList getConvexHull$($double$[][]$ s$)$

MyPoint is a static inner class defined as follows:

private static class MyPoint implements Comparable $\{$

double x$,$ y;

MyPoint rightMostLowestPoint;

MyPoint$($double x$,$ double y$)\{$

this.x $=$ x; this.y $=$ y;

$\}$

public void setRightMostLowestPoint$($MyPoint p$)\{$

rightMostLowestPoint $=$ p;

$\}$

@Override

public int compareTo$($MyPoint o$)\{$

$//$ Implement it to compare this point with point o

$//$ angularly along the x$-$axis with rightMostLowestPoint

$//$ as the center, as shown in Figure $22\mathrm{.}10$b$.$ By implementing

$//$ the Comparable interface, you can use the Array.sort

$//$ method to sort the points to simplify coding.

$\}$

$\}$

Write a test program that prompts the user to enter the set size and the points

and displays the points that form a convex hull.