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.*;
import java.math.*;
import java.awt.geom.*;

import static java.lang.Math.*;

public class Solution implements Runnable {
	
	double rotateX (double x, double y, double angle) {
		return x * cos(angle) - y * sin(angle);  
	}
	
	double rotateY (double x, double y, double angle) {
		return x * sin(angle) + y * cos(angle);
	}
	
	double triangleSquare (double x1, double y1, double x2, double y2, double x3, double y3) {
		return abs ((x2 - x1) * (y2 + y1) + (x3 - x2) * (y3 + y2) + (x1 - x3) * (y1 + y3)) / 2.0;
	}
	
	double getA (double y1, double y2) {
		return y1 - y2;
	}
	
	double getB (double x1, double x2) {
		return x2 - x1;
	}
	
	double getC (double x1, double y1, double x2, double y2) {
		return x1 * y2 - x2 * y1;
	}
	
	public void solve () throws Exception {
		int w = sc.nextInt();
		int h = sc.nextInt();
		if (w < h) {
			int t = w;
			w = h;
			h = t;
		}
		int alpha = sc.nextInt();
		if (alpha > 90) alpha = 180 - alpha;
		if (alpha == 0) {
			out.printf("%.6f", (double) w * h);
			return;
		} else if (alpha == 90) {
			out.printf("%.6f", (double) h * h);
			return;
		}
		double x1 = (double) w / 2.0;
		double y1 = (double) h / 2.0;
		double x2 = x1;
		double y2 = -y1;
		double x3 = -x1;
		double y3 = y2;
		
		double rx1 = rotateX(x1, y1, Math.toRadians(alpha));
		double rx2 = rotateX(x2, y2, Math.toRadians(alpha));
		double rx3 = rotateX(x3, y3, Math.toRadians(alpha));
		double ry1 = rotateY(x1, y1, Math.toRadians(alpha));
		double ry2 = rotateY(x2, y2, Math.toRadians(alpha));
		double ry3 = rotateY(x3, y3, Math.toRadians(alpha));
		
		double upX = (-getC(rx1, ry1, rx2, ry2) - getB(rx1, rx2) * h / 2.0) / getA(ry1, ry2);
		double downX = (-getC(rx3, ry3, rx2, ry2) + getB(rx3, rx2) * h / 2.0) / getA(ry3, ry2);
		double rightUpY = (-getC(rx1, ry1, rx2, ry2) - getA(ry1, ry2) * w / 2.0) / getB(rx1, rx2);
		double rightDownY = (-getC(rx3, ry3, rx2, ry2) - getA(ry3, ry2) * w / 2.0) / getB(rx3, rx2);
		
		double result = (double) w * h;
		
		if (rightUpY + 1e-9 > (double) h / 2.0) {
			upX = (-getC(rx3, ry3, rx2, ry2) - getB(rx3, rx2) * h / 2.0) / getA(ry3, ry2);
			downX = (-getC(rx3, ry3, rx2, ry2) + getB(rx3, rx2) * h / 2.0) / getA(ry3, ry2);
			result -= (double) h * (x1 - upX + x2 - downX); 
		} else {
			result -= 2.0 * triangleSquare(x1, y1, upX, (double) h / 2.0, (double) w / 2.0, rightUpY)
					+ 2.0 * triangleSquare(x2, y2, downX, (double) -h / 2.0, (double) w / 2.0, rightDownY);
		}
		
		out.printf("%.6f", result);	}
	
	
	BufferedReader in;
	PrintWriter out;
	FastScanner sc;

	static Throwable uncaught;

	@Override
	public void run() {
		try {
			in = new BufferedReader(new InputStreamReader(System.in));
			out = new PrintWriter(System.out);
			sc = new FastScanner(in);
			solve();
		} catch (Throwable t) {
			Solution.uncaught = t;
		} finally {
			out.close();
		}
	}

	public static void main(String[] args) throws Throwable {
		Thread t = new Thread(null, new Solution(), "", (1 << 26));
		t.start();
		t.join();
		if (uncaught != null) {
			throw uncaught;
		}
	}

}

class FastScanner {

	BufferedReader reader;
	StringTokenizer strTok;

	public FastScanner(BufferedReader reader) {
		this.reader = reader;
	}

	public String nextToken() throws IOException {
		while (strTok == null || !strTok.hasMoreTokens()) {
			strTok = new StringTokenizer(reader.readLine());
		}
		return strTok.nextToken();
	}

	public int nextInt() throws IOException {
		return Integer.parseInt(nextToken());
	}

	public long nextLong() throws IOException {
		return Long.parseLong(nextToken());
	}

	public double nextDouble() throws IOException {
		return Double.parseDouble(nextToken());
	}

}