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

public class Main {
	
	static double eps = 1e-6;
	static double[] inter(double x1, double y1, double x2, double y2, double x3, double y3, double x4, double y4) {
		double a1 = y1 - y2;
		double b1 = x2 - x1;
		double c1 = x1*y2 - x2*y1;
		double a2 = y3 - y4;
		double b2 = x4 - x3;
		double c2 = x3*y4 - x4*y3;
		
		double aa = b1*c2 - b2*c1;
		double bb = c1*a2 - c2*a1;
		double cc = a1*b2 - a2*b1;

		double xx = aa/cc;
		double yy = bb/cc;

		if ((x1 - xx) * (x2 - xx) < eps && (y1 - yy) * (y2 - yy) < eps && (x3 - xx) * (x4 - xx) < eps && (y3 - yy) * (y4 - yy) < eps)
			return new double[] {xx, yy};
			else return null;

	}

	public static void main(String[] args) throws Exception {
		long time = System.nanoTime();

		double w = next();
		double h = next();
		double al = next();
		if (al > 90) al = 180 - al;

		if (al == 0) {
			out.println(w*h);
			out.close();
			return;
		}

		if (al == 90) {
			out.println(Math.min(h, w) * Math.min(h, w));
			out.close();
			return;
		}
		al *= Math.PI / 180;

		double[] x = new double[] {-w/2, w/2, w/2, -w/2};
		double[] y = new double[] {-h/2, -h/2, h/2, h/2};

		double[] xx = new double[4];
		double[] yy = new double[4];

		for (int i = 0; i < 4; i++) {
			xx[i] = Math.cos(al) * x[i] - Math.sin(al) * y[i];
			yy[i] = Math.sin(al) * x[i] + Math.cos(al) * y[i];
		}

		double[] ix = new double[9];
		double[] iy = new double[9];

		int ind = 0;
		double[] coord;
		for (int i = 0; i < 4; i++)
			for (int j = i; j != (i + 3) % 4; j = (j + 1) & 3) {
//				System.out.println(i + " " + j);
				int ii1 = i;
				int ii2 = (i + 1) & 3;
				int jj1 = j;
				int jj2 = (j + 1) & 3;

				coord = inter(xx[ii1], yy[ii1], xx[ii2], yy[ii2], x[jj1], y[jj1], x[jj2], y[jj2]);
				if (coord != null) {
					ix[ind] = coord[0];
					iy[ind] = coord[1];
//					System.out.println(coord[0] + " " + coord[1]);
					ind++;
				}
			}
		
		ix[ind] = ix[0];
		iy[ind] = iy[0];
		double sq = 0;
		for (int i = 0; i < ind; i++) sq += ix[i + 1] * iy[i] - ix[i] * iy[i + 1];
		out.println(-sq/2);
		
//		System.out.println((System.nanoTime() - time)* 1e-9);
		out.close();
	}
	static PrintWriter out = new PrintWriter(System.out);
	
	static BufferedReader bufferedreader = new BufferedReader(new InputStreamReader(System.in));
	static StringTokenizer in = new StringTokenizer("");

	static String nextToken() throws Exception {
		if (!in.hasMoreTokens()) in = new StringTokenizer(bufferedreader.readLine());
		return in.nextToken();
	}

	static int next()  throws Exception {return Integer.parseInt(nextToken());};
	static int[] next(int n) throws Exception {
		int[] x = new int[n];
		for (int i = 0; i < n; i++) x[i] = next();
		return x;
	}
	static int[][] next(int n, int m) throws Exception {
		int[][] x = new int[n][];
		for (int i = 0; i < n; i++) x[i] = next(m);
		return x;
	}

	static long nextl() throws Exception {return Long.parseLong(nextToken());};
	static long[] nextl(int n) throws Exception {
		long[] x = new long[n];
		for (int i = 0; i < n; i++) x[i] = nextl();
		return x;
	}
	static long[][] nextl(int n, int m) throws Exception {
		long[][] x = new long[n][];
		for (int i = 0; i < n; i++) x[i] = nextl(m);
		return x;
	}

	static double nextd() throws Exception {return Double.parseDouble(nextToken());};
	static double[] nextd(int n) throws Exception {
		double[] x = new double[n];
		for (int i = 0; i < n; i++) x[i] = nextd();
		return x;
	}
	static double[][] nextd(int n, int m) throws Exception {
		double[][] x = new double[n][];
		for (int i = 0; i < n; i++) x[i] = nextd(m);
		return x;
	}

	static String nextline() throws Exception {
		in = new StringTokenizer("");
		return bufferedreader.readLine();
	}

}