There are n stones at some integer coordinate points on a 2D plane. Each coordinate point may have at most one stone.
You need to remove some stones.
A stone can be removed if it shares either the same row or the same column as another stone that has not been removed.
Given an array stones of length n where stones[i] = [xi, yi] represents the location of the ith stone, return the maximum possible number of stones that you can remove.

Example 1:
Input:
n=6
[[0 0] ,[ 0 1], [1 0] ,[1 2] ,[2 1] ,[2 2]]
Output:
5
Example:
One way to remove 5 stones are
1--[0,0]
2--[1,0]
3--[0,1]
4--[2,1]
5--[1,2]
Your Task:
You don't need to print or input anything. Complete the function maxRemove() which takes an integer array arr, an integer n as the input parameters and returns an integer, denoting the maximum number of stones that can be removed.

Expected Time Complexity: O(N+K)
Expected Space Complexity: O(K)

Constraints:
1 <= n <=1000
0 <= x[i], y[i]<= 10^{4}
No two stones are at same position.

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