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.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.util.StringTokenizer;

public class Solver {

	public static void main(String[] Args) throws NumberFormatException,
			IOException {
		new Solver().Run();
	}

	PrintWriter pw;
	StringTokenizer Stok;
	BufferedReader br;

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

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

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

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

	double width, height;
	double alfa;
	double result;
	
	class Point{
		
		public double x,y;
		
		public Point(double ax, double ay){
			x=ax;
			y=ay;
		}
	}
	
	public void findPoints(Point t0, Point t1){
		double angle=Math.atan(height/width);
		double ang=alfa - angle;
		double rad=Math.sqrt(height*height/4 + width*width/4);
		t0.x=rad*Math.cos(ang);
		t0.y=rad*Math.sin(ang);
		ang=alfa+angle;
		t1.x=rad*Math.cos(ang);
		t1.y=rad*Math.sin(ang);
	}
	
	public void Run() throws NumberFormatException, IOException {
		//br = new BufferedReader(new FileReader("input.txt")); pw = new PrintWriter("output.txt");
		br=new BufferedReader(new InputStreamReader(System.in));  pw=new PrintWriter(new OutputStreamWriter(System.out));
		
		width=nextInt();
		height=nextInt();
		alfa=nextInt();
		result=height*width;
		
		if (height>width){
			double buf=height;
			height=width;
			width=buf;
		}
		
		if (alfa>90){
			alfa=180-alfa;
		}
		if (Math.abs(alfa)<1e-5){
			pw.println(result);
			pw.flush();
			pw.close();
			return;
		}
		alfa=alfa/360*2*Math.PI;
		
		Point t0new = new Point(0, 0), t1new = new Point(0, 0);
		findPoints(t0new, t1new);
		if (t0new.y>(double)height/2){
			t1new.x*=-1;
			t1new.y*=-1;
			double dx=(t1new.x-t0new.x)/(t1new.y-t0new.y);
			double b1=width/2-(t0new.x+dx*(height/2-t0new.y));
			double b2=width/2-(t0new.x+dx*(-height/2-t0new.y));
			double plos=height*(b1+b2)/2;
			result-=(plos*2);
		}
		else {
			double k=(width/2-t1new.x)/(t0new.x-t1new.x);
			double len=height/2-(k*t0new.y+(1-k)*t1new.y);
			double plos=len*Math.tan(alfa)*len/2;
			result-=(plos*2);
			
			t1new.x*=-1;
			t1new.y*=-1;
			k=(width/2-t1new.x)/(t0new.x-t1new.x);
			len=k*t0new.y+(1-k)*t1new.y+height/2;
			plos=len*Math.tan(Math.PI/2-alfa)*len/2;
			result-=(plos*2);
		}
		pw.println(result);
		pw.flush();
		pw.close();
	}

}