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.

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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.ArrayList;
import java.util.Collections;
import java.util.Scanner;

public class RectanglePuzzle {
	public static class Point implements Comparable<Point> {
		public double x;
		public double y;
		public static double EPS = 1e-7;

		public Point(double x, double y) {
			this.x = x;
			this.y = y;
		}

		@Override
		public int compareTo(Point arg0) {
			double angle = Math.atan2(y, x);
			double otherAngle = Math.atan2(y, x);
			return ((Double) angle).compareTo(otherAngle);
		}

		public String toString() {
			return "x: " + x + ", y: " + y;
		}
	}

	public static class Line {
		public Point P0;
		public Point P1;
		public double a, b, c;

		public String toString() {
			return P0.toString() + P1.toString() + ", a: " + a + ", b: " + b
					+ ", c: " + c+"\n";
		}

		public Line(Point P0, Point P1) {
			this.P0 = P0;
			this.P1 = P1;
			a = P1.y - P0.y;
			b = P0.x - P1.x;
			c = a * P0.x + b * P0.y;
		}

		public boolean isParallel(Line t) {
			double d = a * t.b - b * t.a;
			if (Math.abs(d) < Point.EPS)
				return true;
			else
				return false;
		}

		public boolean isSame(Line t) {
			if (isParallel(t) && c == t.c)
				return true;
			else
				return false;
		}

		public static Point isect(Line s, Line t) {
			if (s.isParallel(t))
				return null;
			double d = s.a * t.b - s.b * t.a;
			double px = (s.c * t.b - s.b * t.c) / d;
			double py = (s.a * t.c - s.c * t.a) / d;
			Point res = new Point(px, py);
			if (s.PointBetween(res) && t.PointBetween(res))
				return res;
			return null;
		}

		public boolean PointBetween(Point p) {
			return (P0.x < p.x && p.x < P1.x) || (P0.y < p.y && p.y < P1.y)
					|| (P0.x > p.x && p.x > P1.x) || (P0.y > p.y && p.y > P1.y);
		}
	}

	public static void main(String[] args) {
		Scanner reader = new Scanner(System.in);
		double h = reader.nextDouble();
		double w = reader.nextDouble();
		int alpha = reader.nextInt();
		alpha = alpha > 90 ? 180 - alpha : alpha;
		if (alpha == 0){
			System.out.println(h*w);
			return;
		}
		ArrayList<Point> orig = new ArrayList<Point>();
		orig.add(new Point(h / 2, w / 2));
		orig.add(new Point(0 - h / 2, w / 2));
		orig.add(new Point(0 - h / 2, 0 - w / 2));
		orig.add(new Point(h / 2, 0 - w / 2));
		ArrayList<Point> rot = new ArrayList<Point>();
		for (Point p : orig) {
			double x = Math.cos(Math.toRadians(alpha)) * p.x
					- Math.sin(Math.toRadians(alpha)) * p.y;
			double y = Math.sin(Math.toRadians(alpha)) * p.x
					+ Math.cos(Math.toRadians(alpha)) * p.y;
			rot.add(new Point(x, y));
		}

		ArrayList<Line> origLines = new ArrayList<Line>();
		origLines.add(new Line(orig.get(3), orig.get(0)));
		for (int i = 0; i < 3; i++) {
			origLines.add(new Line(orig.get(i), orig.get(i + 1)));
		}
		ArrayList<Line> rotLines = new ArrayList<Line>();
		rotLines.add(new Line(rot.get(3), rot.get(0)));
		for (int i = 0; i < 3; i++) {
			rotLines.add(new Line(rot.get(i), rot.get(i + 1)));
		}

		ArrayList<Point> inter = new ArrayList<Point>();
		for (Line o : origLines) {
			for (Line r : rotLines) {
				if (Line.isect(o, r) != null)
					inter.add(Line.isect(o, r));
			}
		}

		Collections.sort(inter);
		Point tmp = inter.get(0);
		inter.set(0, inter.get(1));
		inter.set(1, tmp);
		//System.out.println("orig :" + orig.toString());
		//System.out.println("rot :" + rot.toString());
		//System.out.println("origlines :" + origLines.toString());
		//System.out.println("rotlines :" + rotLines.toString());
		//System.out.println("Inter :" + inter.toString());

		
		
		double area = 0;
		for (int i = 0; i < inter.size(); i++) {
			area += inter.get(i).x * inter.get((i + 1) % inter.size()).y;
			area -= inter.get(i).y * inter.get((i + 1) % inter.size()).x;
		}
		area /= 2;
		area = Math.abs(area);
		System.out.println(area);
	}
}