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.List;
import java.io.IOException;
import java.io.InputStreamReader;
import java.awt.geom.Line2D;
import java.awt.geom.Point2D;
import java.util.ArrayList;
import java.io.PrintStream;
import java.io.BufferedReader;
import java.util.Comparator;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.util.StringTokenizer;
import java.util.Collection;
import java.util.Collections;
import java.io.InputStream;

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

class TaskA {
    public ArrayList<Point2D> getIntersections(Line2D l1,double w,double h) {
        ArrayList<Point2D> answer=new ArrayList<Point2D>();
        ArrayList<Line2D> lines=new ArrayList<Line2D>();
        lines.add(new Line2D.Double(-w/2,h/2,w/2,h/2));
        lines.add(new Line2D.Double(w/2,h/2,w/2,-h/2));
        lines.add(new Line2D.Double(w/2,-h/2,-w/2,-h/2));
        lines.add(new Line2D.Double(-w/2,-h/2,-w/2,h/2));
        for(int i=0;i<lines.size();i++) {
            Point2D P=LineUtils.getIntersection(lines.get(i),l1);
            if(P!=null && l1.intersectsLine(lines.get(i))) {
               answer.add(P);
            }
        }
        return answer;
    }
    public void solve(int testNumber, InputReader in, PrintWriter out) {
        double w=in.nextDouble();
        double h=in.nextDouble();
        double a=in.nextDouble();
        if(a==0 || a==180) {
            out.println(w*h);
            return;
        }
        if(a==90) {
            out.println(Math.min(w,h)*Math.min(w,h));
            return;
        }

        a=a/180*Math.PI;
        double length=Math.sqrt(w*w/4+h*h/4);
        double startAlpha=Math.atan2(h/2,w/2) ;
        Point2D p1=new Point2D.Double(length*Math.cos(startAlpha+a),length*Math.sin(startAlpha+a));
        Point2D p2=new Point2D.Double(length*Math.cos(2*(Math.PI/2-startAlpha)+startAlpha+a),length*Math.sin(2*(Math.PI/2-startAlpha)+startAlpha+a));
        Point2D p3=new Point2D.Double(length*Math.cos(Math.PI+startAlpha+a),length*Math.sin(Math.PI+startAlpha+a));
        Point2D p4=new Point2D.Double(length*Math.cos(-startAlpha+a),length*Math.sin(-startAlpha+a));
        Line2D l1=new Line2D.Double(p1,p2);
        Line2D l2=new Line2D.Double(p2,p3);
        Line2D l3=new Line2D.Double(p3,p4);
        Line2D l4=new Line2D.Double(p4,p1);
        ArrayList<Point2D> points=new ArrayList<Point2D>();
        points.addAll(getIntersections(l1,w,h));
        points.addAll(getIntersections(l2,w,h));
        points.addAll(getIntersections(l3,w,h));
        points.addAll(getIntersections(l4,w,h));
        System.out.println();
        Collections.sort(points,new MyComparator());
       // System.out.println(PointUtils.getAlpha(points.get(0)));
     //   System.out.println(PointUtils.getAlpha(points.get(1)));
        double area=0;
        for(int i=0;i<points.size();i++) {
            Point2D nextPoint=(i==points.size()-1)?points.get(0):points.get(i+1);
            Line2D l=new Line2D.Double(points.get(i),nextPoint);
            double d=l.ptLineDist(new Point2D.Double(0,0));
            if(Math.abs(d-w/2)>Math.abs(d-h/2)) {
                d=h/2;
            }
            else d=w/2;
            area+=d* LineUtils.getLength(l)/2;

        }
        out.println(area);

    }
}

class MyComparator implements Comparator<Point2D>
{

    public int compare(Point2D point2D, Point2D point2D1)
    {
        double dif=PointUtils.getAlpha(point2D)-PointUtils.getAlpha(point2D1);
        if(dif<0)return -1;
        if(dif==0) return 0;
        return 1;
    }

    public boolean equals(Object o)
    {
      return false;
    }
}

class LineUtils
{

    // return line of the form AX+BY=C
    public static double getA(Line2D l) {
        return l.getY2()-l.getY1();
    }

    public static double getB(Line2D l) {
        return l.getX1()-l.getX2();
    }

    public static double  getC(Line2D l) {
        return getA(l)*l.getX1()+getB(l)*l.getY1();
    }

    public static Point2D getIntersection(Line2D l1,Line2D l2) {
        double det = getA(l1)*getB(l2) - getA(l2)*getB(l1);
        if(det == 0){
            return null;
        }else{
            double x = (getB(l2)*getC(l1) - getB(l1)*getC(l2))/det;
            double y = (getA(l1)*getC(l2) - getA(l2)*getC(l1))/det;
            return new Point2D.Double(x,y);
        }

    }

    public static double getLength(Line2D l) {
        return Math.sqrt( (l.getX1()-l.getX2())*(l.getX1()-l.getX2())+(l.getY1()-l.getY2())*(l.getY1()-l.getY2()) );
    }
}

class InputReader {
    StringTokenizer st;
    BufferedReader in;
    public InputReader(InputStream ins)
    {
        in = new BufferedReader(new InputStreamReader(ins));
    }

    public String nextToken()
    {
        while(st==null || !st.hasMoreTokens())
        {
            try {
                st=new StringTokenizer(in.readLine());
            } catch (IOException e) {
                e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
            }
        }
        return st.nextToken();
    }

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

}

class PointUtils
{
    public static double getAlpha(Point2D p) {
        double alpha=Math.atan2(p.getY(),p.getX());
        if(alpha<0) alpha= Math.PI*2-Math.abs(alpha);
        return alpha;
    }
}