Example 1:
Input: points = [[0,0],[1,0],[2,0],[10,0]], d = 2
Output: 2
Explanation:
Example 2:
Input: points = [[0,0],[3,0],[0,4]], d = 6
Output: 1
Explanation:
Example 3:
Input: points = [[0,0],[2,0],[4,0]], d = 2
Output: 3
Explanation:
You are given points, where points[i] = [x_i, y_i] is the position of the ith ball on a 2D plane, and an integer d.
Two balls are directly attracted to each other if the Euclidean distance between them is strictly less than d.
Attraction causes a chain reaction: if ball a attracts ball b, and ball b attracts ball c, then starting from any one of those balls will eventually absorb all three balls during the same second.
In one second, you may choose one ball that has not been absorbed yet and start the attraction process from it.
Return the minimum number of seconds needed to absorb all balls.
Balls 0, 1, and 2 form one connected component because 0 <-> 1 and 1 <-> 2 each have distance strictly less than 2. Ball 3 is isolated, so two activations are needed.
Every ball belongs to the same connected component because all pairwise distances are strictly less than 6.
The distance between adjacent balls is exactly 2, which does not qualify because the rule is strictly less than d.
1 <= points.length <= 1000points[i].length == 2-10^6 <= x_i, y_i <= 10^61 <= d <= 10^6