import java.util.*;
import java.io.*;
import java.awt.geom.*;

public class K {
	
	
	double signedDist(double x1, double y1, double x2, double y2, double x, double y) {
		double dist = Line2D.ptLineDist(x1, y1, x2, y2, x, y);
		
		double px = x2-x1;
		double py = y2-y1;
		double qx = x-x1;
		double qy = y-y1;
		
		//positive side or negative side!
		if(px*qy - py*qx>0) return dist;
		else return -dist;
	}
	
	public void doIt() throws Exception {
		Scanner sc = new Scanner(System.in);
		PrintStream ps = System.out;
		
		for(int testno=1;;testno++) {
			int n = sc.nextInt();
			if(n==0) break;
			
			double xs[] = new double[n];
			double ys[] = new double[n];
			for(int i=0;i<n;i++) {
				xs[i] = sc.nextDouble();
				ys[i] = sc.nextDouble();
			}
			
			double best = 1e100;
			for(int i=0;i<n;i++) for(int j=i+1;j<n;j++) {
				double maxDist = -1;
				double minDist = 1;
				
				for(int k=0;k<n;k++) {
					double dist = signedDist(xs[i], ys[i], xs[j], ys[j], xs[k], ys[k]);
					
					minDist = Math.min(dist, minDist);
					maxDist = Math.max(dist, maxDist);
				}
				
				double diff = maxDist - minDist;
				best = Math.min(best, diff);
			}
			
			ps.printf("Case %d: %.2f\n", testno, best);
		}
		
	}
	
	public static void main(String args[]) throws Exception {
		(new K()).doIt();
	}
}