// Arup Guha
// 4/34/2013
// Solution to 2013 UCF High School Contest Problem: Squirrel Territory

import java.util.*;
import java.io.*;

public class squirrels {
	
	public static void main(String[] args) throws Exception {
		
		Scanner fin = new Scanner(new File("squirrels.in"));
		int n = fin.nextInt();
		
		// Go through all the cases.
		for (int loop=1; loop<=n; loop++) {
			
			// Get all the trees.
			int size = fin.nextInt();
			double[][] centers = new double[size][2];
			for (int i=0; i<size; i++) {
				centers[i][0] = fin.nextInt();
				centers[i][1] = fin.nextInt();
			}
			
			// Find the minimum distance between and two trees.
			double maxD = 10000000;
			for (int i=0; i<size; i++) {
				for (int j=i+1; j<size; j++) {
					if (dist(centers[i],centers[j]) < maxD)
						maxD = dist(centers[i],centers[j]);
				}
			}
			
			// For these two trees, the best we can hope for are two areas that
			// meet in the middle.
			double maxR = maxD/2.0;
			double area = Math.PI*maxR*maxR;
			
			// Output this case.
			System.out.printf("Campus #%d:\n", loop);
			System.out.printf("Maximum territory area = %.3f\n\n", area);
		}
	}
	
	// Distance formula between pts a and b.
	public static double dist(double[] a, double[] b) {
		return Math.sqrt(Math.pow(a[0]-b[0],2) + Math.pow(a[1]-b[1],2));
	}

}