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.OutputStream;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.InputMismatchException;
import java.awt.geom.Point2D;
import java.io.Writer;
import java.io.InputStream;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 * @author emotionalBlind
 */
public class Main {
	public static void main(String[] args) {
		InputStream inputStream = System.in;
		OutputStream outputStream = System.out;
		InputReader in = new InputReader(inputStream);
		OutputWriter out = new OutputWriter(outputStream);
		TaskA solver = new TaskA();
		solver.solve(1, in, out);
		out.close();
	}
}

class TaskA {
    static final double EPS = 1e-10;
    boolean inside(double w, double h, Point2D p) {
        if (p.getX() + EPS < -w/2) return false;
        if (p.getX() - EPS > w/2) return false;
        if (p.getY() + EPS < -h/2) return false;
        if (p.getY() - EPS > h/2) return false;
        return true;
    }

    public void solve(int testNumber, InputReader in, OutputWriter out) {
        double w = in.readInt();
        double h = in.readInt();
        if (w < h) {
            double temp = w;
            w = h;
            h = temp;
        }
        int deg = in.readInt();

        if (deg == 90) {
            double res = h * h;
            out.printLine(res);
            return;
        }
        if (deg == 0 || deg == 180) {
            double res = w * h;
            out.printLine(res);
            return;
        }
        if (deg > 90) deg = 180 - deg;

        double angle = (Math.PI * deg) / 180.;
        Point2D.Double[] points = new Point2D.Double[4];
        points[0] = new Point2D.Double(-w/2, h/2);
        points[1] = new Point2D.Double(w/2, h/2);
        points[2] = new Point2D.Double(w/2, -h/2);
        points[3] = new Point2D.Double(-w/2, -h/2);

        Point2D.Double[] points_new = new Point2D.Double[4];
        for (int i = 0; i < points.length; ++i) {
            double x = points[i].getX() * Math.cos(angle) - points[i].getY() * Math.sin(angle);
            double y = points[i].getX() * Math.sin(angle) + points[i].getY() * Math.cos(angle);
            points_new[i] = new Point2D.Double(x, y);
        }

        Line[] lines = new Line[4];
        Line[] lines_new = new Line[4];
        for (int i = 0; i < 4; ++i) {
            int u = i;
            int v = (i + 1) % 4;
            lines[i] = new Line(points[u].getX(), points[u].getY(), points[v].getX(), points[v].getY());
            lines_new[i] = new Line(points_new[u].getX(), points_new[u].getY(), points_new[v].getX(), points_new[v].getY());
        }

        int k = 0;
        Point2D.Double[] poly = new Point2D.Double[100];
        for (int i = 0; i < 4; ++i) {
            int before = (i + 2) % 4;
            Point2D.Double p0 = lines_new[i].getIntersectingPoint(lines[before]);
            if (inside(w, h, p0)) poly[k++] = p0;
            int first = (i + 3) % 4;
            Point2D.Double p1 = lines_new[i].getIntersectingPoint(lines[first]);
            if (inside(w, h, p1)) poly[k++] = p1;
            int second = (i) % 4;
            Point2D.Double p2 = lines_new[i].getIntersectingPoint(lines[second]);
            if (inside(w, h, p2)) poly[k++] = p2;
        }

        double area = 0;
        for (int i = 0; i < k; ++i) {
            int ni = i + 1;
            if (ni == k) ni = 0;
            area +=  poly[i].getX() * poly[ni].getY();
            area -=  poly[ni].getX() * poly[i].getY();
        }
        area = Math.abs(area) / 2.0;
        out.printLine(area);
    }
}

class InputReader {

    private InputStream stream;
    private byte[] buf = new byte[1024];
    private int curChar;
    private int numChars;

    public InputReader(InputStream stream) {
        this.stream = stream;
    }

    public int read() {
        // InputMismatchException -> UnknownError
        if (numChars == -1)
            throw new UnknownError();
        if (curChar >= numChars) {
            curChar = 0;
            try {
                numChars = stream.read(buf);
            } catch (IOException e) {
                throw new UnknownError();
            }
            if (numChars <= 0)
                return -1;
        }
        return buf[curChar++];
    }

    public int readInt() {
        int c = read();
        while (isSpaceChar(c))
            c = read();
        int sgn = 1;
        if (c == '-') {
            sgn = -1;
            c = read();
        } else if (c == '+') {
            c = read();
        }
        int res = 0;
        do {
            if (c < '0' || c > '9')
                throw new InputMismatchException();
            res *= 10;
            res += c - '0';
            c = read();
        } while (!isSpaceChar(c));
        return res * sgn;
    }

    public static boolean isSpaceChar(int c) {
        return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
    }

    }

class OutputWriter {
    private final PrintWriter writer;

    public OutputWriter(OutputStream outputStream) {
        writer = new PrintWriter(outputStream);
    }

    public OutputWriter(Writer writer) {
        this.writer = new PrintWriter(writer);
    }

    public void print(Object...objects) {
        for (int i = 0; i < objects.length; i++) {
            if (i != 0)
                writer.print(' ');
            writer.print(objects[i]);
        }
    }

    public void printLine(Object...objects) {
        print(objects);
        writer.println();
    }

    public void close() {
        writer.close();
    }

}

class Line {
    double a;
    double b;
    double c;

    public Line(double a, double b, double c) {
        this.a = a;
        this.b = b;
        this.c = c;
    }

    public Line(double x1, double y1, double x2, double y2) {
        this.a = y1 - y2;
        this.b = x2 - x1;
        this.c = y1 * (x1 - x2) - x1 * (y1 - y2);
    }

    public Point2D.Double getIntersectingPoint(Line that) {
        double x = (this.b * that.c - that.b * this.c) / (this.a * that.b - that.a * this.b);
        double y = (that.a * this.c - this.a * that.c) / (this.a * that.b - that.a * this.b);
        Point2D.Double point = new Point2D.Double(x, y);
        return point;
    }
}