Angular Sweep Algorithm in C++

In this article, we will discuss the Angular Sweep Algorithm in C++ with its implementation.

It means that we need to determine the greatest number of points that are included (lying inside the circle rather than on its borders) by a circle of radius r given a set of 2-D points. For this, the angular sweep algorithm is the most efficient technique. In computational geometry, the Angular Sweep Algorithm is used for several purposes, including determining the convex hull of a set of points.

The convex hull of a set of points can be found using the Angular Sweep Algorithm in the following examples:

Example 1:

Input: {{0, 3}, {1, 1}, {2, 2}, {4, 4}, {0, 0}, {1, 2}, {3, 1}, {3, 3}}

Output: {(0, 0), (0, 3), (4, 4), (3, 1), (3, 3)}

Example 2:

Input: {{0, 0}, {1, 1}, {2, 2}, {3, 3}, {4, 4}}

Output: {(0, 0), (4, 4), (3, 3)}

It determines the greatest number of points that a fixed-radius circle with radius "R" may surround given "n" points on a 2-Dimensional plane.

Note: Even if a point is on the circumference, it is still regarded as being inside the circle.

As an example:

Input: R = 1

points[] = {(8.65844, 5.67258), (4.25496 6.94715), (7.68547 7.58552)}

Output: 2

The maximum number of points is 2,

Program:

Let us take an example to illustrate the Angular Sweep Algorithm in C++.

Output: