content: package v002;
  
  import java.io.BufferedReader;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.InputStreamReader;
  import java.io.PrintWriter;
  import java.util.Arrays;
  import java.util.StringTokenizer;
  
  public class MothEradication_UVa218 {
  		
  	static final double EPS = 1e-9;
  	
  	public static void main(String[] args) throws IOException {
  		
  		Scanner sc = new Scanner(System.in);
  		PrintWriter out = new PrintWriter(System.out);
  		int k = 1;
  		while(true)
  		{
  			int n = sc.nextInt();
  			if(n == 0) break;
  			if(k != 1)
  				out.println();
  			out.format("Region #%d:\n", k++);
  			
  			Point[] points = new Point[n];
  			for(int i = 0; i < n; i++)
  				points[i] = new Point(sc.nextDouble(), sc.nextDouble());
  			
  			Polygon p = new Polygon(points);
  			for(int i = p.g.length - 1; i >= 0; i--)
  			{
  				out.format("(%.1f,%.1f)", p.g[i].x, p.g[i].y);
  				if(i != 0)
  					out.print('-');
  			}
  			out.format("\nPerimeter length = %.2f\n", p.perimeter());
  		}
  		out.flush();
  		
  	}
  	
  	static class Point implements Comparable<Point>
  	{
  		double x, y;
  		
  		Point(double a, double b)
  		{
  			x = a; y = b;
  		}
  		
  		public int compareTo(Point p)
  		{
  			if(Math.abs(x - p.x) > EPS)
  				return x > p.x ? 1 : -1;
  			if(Math.abs(y - p.y) > EPS)
  				return y > p.y  ? 1 : -1;
  			return 0;
  		}
  		
  		double dist(Point p)
  		{
  			return Math.sqrt((p.x - x) * (p.x - x) + (p.y - y) * (p.y - y));
  		}
  	}
  	
  	static class Vector
  	{
  		double x, y;
  		
  		Vector(Point p, Point q)
  		{
  			x = q.x - p.x;
  			y = q.y - p.y;
  		}
  		
  		double cross(Vector v)
  		{
  			return x * v.y - y * v.x;
  		}
  		
  		double dot(Vector v)
  		{
  			return x * v.x + y * v.y;
  		}
  		
  		double norm2()
  		{
  			return x * x + y * y;
  		}
  	}
  	
  	static double angle(Point a, Point o, Point b)
  	{
  		Vector oa = new Vector(o, a), ob = new Vector(o, b);
  		return Math.acos(oa.dot(ob) / Math.sqrt(oa.norm2() * ob.norm2()));
  	}
  	static boolean ccw(Point p, Point q, Point r)
  	{
  		return new Vector(p, q).cross(new Vector(p, r)) + EPS >= 0;
  	}
  	
  	static class Polygon
  	{
  		Point[] g;
  		
  		Polygon(Point[] points)
  		{
  			Arrays.sort(points);
  			int n = points.length;
  			g = new Point[n<<1];
  			int size = 0, start = 0;
  			
  			for(int i = 0; i < n; i++)
  			{
  				Point p = points[i];
  				while(size - start >= 2 && !ccw(g[size-2], g[size-1], p)) size--;
  				g[size++] = p;
  			}
  			start = --size;
  			
  			for(int i = n - 1; i >= 0; i--)
  			{
  				Point p = points[i];
  				while(size - start >= 2 && !ccw(g[size-2], g[size-1], p)) size--;
  				g[size++] = p;
  			}
  			
  			g = Arrays.copyOf(g, size);
  		}
  		
  		double perimeter()
  		{
  			double sum = 0.0;
  			for(int i = 0; i < g.length - 1; i++)
  				sum += g[i].dist(g[i+1]);
  			return sum;
  		}
  		
  	}
  	
  	static class Scanner 
  	{
  		StringTokenizer st;
  		BufferedReader br;
  
  		public Scanner(InputStream s){	br = new BufferedReader(new InputStreamReader(s));}
  
  		public String next() throws IOException 
  		{
  			while (st == null || !st.hasMoreTokens()) 
  				st = new StringTokenizer(br.readLine());
  			return st.nextToken();
  		}
  
  		public int nextInt() throws IOException {return Integer.parseInt(next());}
  		
  		public long nextLong() throws IOException {return Long.parseLong(next());}
  
  		public String nextLine() throws IOException {return br.readLine();}
  		
  		public double nextDouble() throws IOException
  		{
  			String x = next();
  			StringBuilder sb = new StringBuilder("0");
  			double res = 0, f = 1;
  			boolean dec = false, neg = false;
  			int start = 0;
  			if(x.charAt(0) == '-')
  			{
  				neg = true;
  				start++;
  			}
  			for(int i = start; i < x.length(); i++)
  				if(x.charAt(i) == '.')
  				{
  					res = Long.parseLong(sb.toString());
  					sb = new StringBuilder("0");
  					dec = true;
  				}
  				else
  				{
  					sb.append(x.charAt(i));
  					if(dec)
  						f *= 10;
  				}
  			res += Long.parseLong(sb.toString()) / f;
  			return res * (neg?-1:1);
  		}
  		
  		public boolean ready() throws IOException {return br.ready();}
  
  
  	}
  }
  