public class Solution
extends Object
1453 - Maximum Number of Darts Inside of a Circular Dartboard\.
Hard
Alice is throwing `n` darts on a very large wall. You are given an array `darts` where darts[i] = [xi, yi] is the position of the ith dart that Alice threw on the wall.
Bob knows the positions of the `n` darts on the wall. He wants to place a dartboard of radius `r` on the wall so that the maximum number of darts that Alice throws lies on the dartboard.
Given the integer `r`, return _the maximum number of darts that can lie on the dartboard_.
**Example 1:**
**Input:** darts = \[\[-2,0],[2,0],[0,2],[0,-2]], r = 2
**Output:** 4
**Explanation:** Circle dartboard with center in (0,0) and radius = 2 contain all points.
**Example 2:**
**Input:** darts = \[\[-3,0],[3,0],[2,6],[5,4],[0,9],[7,8]], r = 5
**Output:** 5
**Explanation:** Circle dartboard with center in (0,4) and radius = 5 contain all points except the point (7,8).
**Constraints:**
* `1 <= darts.length <= 100`
* `darts[i].length == 2`
* -104 <= xi, yi <= 104
* `1 <= r <= 5000`