Cluster Features

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Advanced Data Structures, Data Structures, Fenwick tree, Line Sweep Technique, Medium, Segment Trees, offline
Problem

Given n 2-dimensional data objects or points in a cluster, we can define the centroid \((x_0, y_0),\) radius R and diameter D of the cluster as follows.

\(x_0 = \frac{\sum\limits_{i=1}^{n}x_i}{n}, y_0 = \frac{\sum\limits_{i=1}^{n}y_i}{n}\)

\(R = \sqrt{\frac{\sum\limits_{i=1}^{n}(x_i - x_0)^2 + (y_i - y_0)^2}{n}}\)

\(D = \sqrt{\frac{\sum\limits_{i=1}^{n}\sum\limits_{j=1}^{n}(x_i - x_j)^2 + (y_i - y_j)^2}{n(n-1)}}\)

where R is the average distance from member objects to the centroid, and D is the average pairwise distance within the cluster. Both R and D reflect the tightness of the cluster around the centroid.

Note: Take \(R = 0\) for \(n \lt 1,\) and \(D = 0\) for \(n \lt 2\)


Given p data objects or points, you are supposed to answer q queries. In the \(i^{th}\) query, you consider only the points whose x-coordinate lies in \([x_{1i}, x_{2i}]\) and y-coordinate lies in \([y_{1i}, y_{2i}]\) as a single cluster. For each query you have to find the centroid, radius and diameter of the cluster. Since the values can be non-integer, you have to print the value of \(nx_0 + ny_0 + n^2R^2 + n(n-1)D^2\)

Constraints

  • \(1 \le p, q \le 15 \times 10^4\)
  • \(1 \le x_i, y_i\le 2 \times 10^4\)
  • \(1 \le x_{1i} \le x_{2i} \le 2 \times 10^4\)
  • \(1 \le y_{1i} \le y_{2i} \le 2 \times 10^4\)

Input Format

The first line contains two integers p and q denoting the number of data objects or points and the number of queries/clusters respectively.

Next p lines contains two-space separated integers denoting \(x_i\) and \(y_i\). The coordinates of \(i^{th}\) data point.

Next q line contains four space-separated integer denoting \(x_{1i}, x_{2i}, y_{1i}, \text{and } y_{2i}\) respectively.

Output Format

Output q lines each containing a single integer. \(i^{th}\) line denotes the value of \(nx_0 + ny_0 + n^2R^2 + n(n-1)D^2\) of the \(i^{th}\) cluster.

Time Limit: 2
Memory Limit: 256
Source Limit:
Explanation

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All the points inside yellow region(including blue) are in the cluster 1:

For cluster 1: data points are \({(2, 4), (5, 3), (5, 5)}\)

  • \(n = 3\) (number of points in the cluster)
  • \((x_0, y_0) = (\frac{2 + 5 + 5}{3}, \frac{4 + 3 + 5}{3}) = (4, 4)\)
  • \(R = \sqrt{\frac{8}{3}}\)
  • \(D = \sqrt{\frac{24}{3}}\)
  • \(nx_0 + ny_0 + n^2R^2 + n(n-1)D^2 = 96\)

All the points inside blue region are in the cluster 2:

For cluster 2: data points are \({(5, 3), (5, 5)}\)

  • \(n = 2\)
  • \((x_0, y_0) = (\frac{5 + 5}{2}, \frac{3 + 5}{2}) = (5, 4)\)
  • \(R = 1\)
  • \(D = 2\)
  • \(nx_0 + ny_0 + n^2R^2 + n(n-1)D^2 = 30\)
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