Problem: You are given two rectangles on a plane. The centers of both rectangles are located in the origin of coordinates (meaning the center of the rectangle's symmetry). The first rectangle's sides are parallel to the coordinate axes: the length of the side that is parallel to the Ox axis, equals w, the length of the side that is parallel to the Oy axis, equals h. The second rectangle can be obtained by rotating the first rectangle relative to the origin of coordinates by angle α.

<image>

Your task is to find the area of the region which belongs to both given rectangles. This region is shaded in the picture.

Input

The first line contains three integers w, h, α (1 ≤ w, h ≤ 106; 0 ≤ α ≤ 180). Angle α is given in degrees.

Output

In a single line print a real number — the area of the region which belongs to both given rectangles.

The answer will be considered correct if its relative or absolute error doesn't exceed 10 - 6.

Examples

Input

1 1 45


Output

0.828427125


Input

6 4 30


Output

19.668384925

Note

The second sample has been drawn on the picture above.

Solution (in JAVA):

Solution:
import java.awt.*;
import java.awt.geom.*;
import java.io.*;
import java.math.*;
import java.text.*;
import java.util.*;


/*
	br = new BufferedReader(new FileReader("input.txt"));
	pw = new PrintWriter(new BufferedWriter(new FileWriter("output.txt")));
	br = new BufferedReader(new InputStreamReader(System.in));
	pw = new PrintWriter(new BufferedWriter(new OutputStreamWriter(System.out)));

 */

public class Main {
	private static BufferedReader br;
	private static StringTokenizer st;
	private static PrintWriter pw;

	public static void main(String[] args) throws IOException	{
		br = new BufferedReader(new InputStreamReader(System.in));
		pw = new PrintWriter(new BufferedWriter(new OutputStreamWriter(System.out)));
		//int qq = 1;
		int qq = Integer.MAX_VALUE;
		//int qq = readInt();
		for(int casenum = 1; casenum <= qq; casenum++)	{
			double w = readDouble()/2;
			double h = readDouble()/2;
			double alpha1 = Math.atan2(h,w);
			Area a = create(w,h,alpha1,readDouble()*Math.PI/180);
			pw.println(computeArea(a));
		}
		pw.close();
	}

	public static Area create(double w, double h, double alpha, double inc)	{
		double r = Math.hypot(w,h);
		double[] pts = new double[8];
		pts[0] = r * Math.cos(alpha);
		pts[2] = r * Math.cos(Math.PI - alpha);
		pts[4] = r * Math.cos(alpha + Math.PI);
		pts[6] = r * Math.cos(Math.PI - (alpha + Math.PI));
		pts[1] = r * Math.sin(alpha);
		pts[3] = r * Math.sin(Math.PI - alpha);
		pts[5] = r * Math.sin(alpha + Math.PI);
		pts[7] = r * Math.sin(Math.PI - (alpha + Math.PI));
		Area one = makeArea(pts);
		for(int i = 0; i < 8; i += 2)	{
			double ang = Math.atan2(pts[i+1], pts[i]);
			ang += inc;
			pts[i] = Math.cos(ang) * r;
			pts[i+1] = Math.sin(ang) * r;
		}
		one.intersect(makeArea(pts));
		return one;
	}
	
	public static Area makeArea(double[] pts) {
		Path2D.Double p = new Path2D.Double();
		p.moveTo(pts[0], pts[1]);
		for (int i = 2; i < pts.length; i += 2) p.lineTo(pts[i], pts[i+1]);
		p.closePath();
		return new Area(p);
	}
	
	public static double[] computeCentroid(double[] x, double[] y)	{
		double xx = 0;
		double yy = 0;
		for(int i = 0; i < x.length; i++)	{
			int j = i+1;
			if(j >= x.length)	{
				j -= x.length;
			}
			xx += (x[i] + x[j])*(x[i]*y[j]-x[j]*y[i]);
			yy += (y[i] + y[j])*(x[i]*y[j]-x[j]*y[i]);
		}
		double A = computePolygonArea(x,y);
		return new double[]{xx/(6*A),yy/(6*A)};
	}
	
	public static double computePolygonArea(double[] x, double[] y)	{
		double ret = 0;
		for(int i = 0; i < x.length; i++)	{
			int j = (i+1);
			if(j >= x.length)
				j -= x.length;
			ret += x[i] * y[j] - x[j] * y[i];
		}
		return ret/2;
	}
	
	public static double computePolygonArea(ArrayList<Point2D.Double> points) {
		Point2D.Double[] pts = points.toArray(new Point2D.Double[points.size()]);
		double area = 0;
		for (int i = 0; i < pts.length; i++){
			int j = (i+1) % pts.length;
			area += pts[i].x * pts[j].y - pts[j].x * pts[i].y;
		}
		return Math.abs(area)/2;
	}
	public static double computeArea(Area a) {
		double ret = 0;
		PathIterator iter = a.getPathIterator(null);
		double[] buffer = new double[6];
		ArrayList<Double> ps = new ArrayList<Double>();
		while (!iter.isDone()) {
			switch (iter.currentSegment(buffer)) {
			case PathIterator.SEG_MOVETO:
			case PathIterator.SEG_LINETO:
				ps.add(buffer[0]);
				ps.add(buffer[1]);
				break;
			case PathIterator.SEG_CLOSE:
				ps.add(ps.get(0));
				ps.add(ps.get(1));
				Double[] qs = ps.toArray(new Double[0]);
				for (int i = 0; i + 2 < ps.size(); i += 2) {
					ret -= qs[i] * qs[i + 3] - qs[i + 1] * qs[i + 2];
				}
				ps.clear();
				break;
			}
			iter.next();
		}
		return ret/2;
	}
	
	private static long readLong() throws IOException	{
		return Long.parseLong(nextToken());
	}

	private static double readDouble() throws IOException	{
		return Double.parseDouble(nextToken());
	}

	private static int readInt() throws IOException	{
		return Integer.parseInt(nextToken());
	}

	private static String nextToken() throws IOException	{
		while(st == null || !st.hasMoreTokens())	{
			if(!br.ready())	{
				pw.close();
				System.exit(0);
			}
			st = new StringTokenizer(br.readLine().trim());
		}
		return st.nextToken();
	}
}