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.util.*;
import java.io.*;
import java.text.NumberFormat;

public class Main
{
	static double w;
	static double h;
	static double a;

	public static void main(String[] args)
	{
		FastScanner in = new FastScanner(System.in);
		w = in.nextInt();
		h = in.nextInt();
		a = in.nextInt();
		if (w < h)
		{
			double tmp = w;
			w = h;
			h = tmp;
		}
		if (a > 90)
			a = 180 - a;
		
		a = a*3.14159265358979 / 180.0 ;

		double area = 0;
		if (a == 0)
		{
//			System.out.println(1);
			area = h * w;
		}
		else if (a < 2 * Math.atan(h / w))
		{
//			System.out.println("a = " + a);
//			System.out.println("Math.atan(h / w) " + Math.atan(h / w));
//			System.out.println(2);
			Point point1 = new Point(w/2, -(w/(2 * Math.tan(a))) + w / (2 * Math.sin(a)));
			Point point2 = new Point(Math.tan(a) * (w / (2 * Math.sin(a)) - h/2), h/2);
			Point point3 = new Point((h/2 - h/(2 * Math.cos(a))) / Math.tan(a), h/2);
			Point point4 = new Point(-w/2, -Math.tan(a) * w / 2 + (h / (2 * Math.cos(a))));
			Point point5 = point1.negate();
			Point point6 = point2.negate();
			Point point7 = point3.negate();
			Point point8 = point4.negate();
			area += area(point1, point2);
			area += area(point2, point3);
			area += area(point3, point4);
			area += area(point4, point5);
			area += area(point5, point6);
			area += area(point6, point7);
			area += area(point7, point8);
			area += area(point8, point1);
		}
		else if (a > 2 * Math.atan(h / w))
		{
//			System.out.println(4);
			area = h * h / Math.sin(a);
		}
		else
		{
			int cant = 0;
			area /= cant;
		}
		System.out.println(area);
	}
	static double area(Point p1, Point p2)
	{
		return Math.abs((p1.x * p2.y) - (p2.x * p1.y)) / 2;
	}

}
class Point
{
	double x;
	double y;
	Point(double x, double y)
	{
		this.x = x;
		this.y = y;
	}
	Point negate()
	{
		return new Point(-x, -y);
	}

}
class FastScanner
{
	BufferedReader reader;
	StringTokenizer tokenizer;
	FastScanner(InputStream inputStream)
	{
		this.reader = new BufferedReader(new InputStreamReader(inputStream));
	}
	String nextToken()
	{
		while (tokenizer == null || ! tokenizer.hasMoreTokens())
		{
			try { tokenizer = new StringTokenizer(reader.readLine());
			} catch (Exception e){}
		}
		return tokenizer.nextToken();
	}
	int nextInt()
	{
		return Integer.parseInt(nextToken());
	}

}