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.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.StringTokenizer;


public class Rectangle {

	/**
	 * @param args
	 */
	
	static double w;
	static double h;
	static double alfa;
	static double area;
	
	public static void main(String[] args) {
		Parser p = new Parser(System.in);
		PrintWriter pw = new PrintWriter(System.out);
		
		w = p.nextInt();
		h = p.nextInt();
		alfa = p.nextInt();
		
		if(alfa == 0 || alfa == 180){
			pw.print(w*h);
			pw.close();
			return;
		}
		if( h > w){
			double tmp = h;
			h = w;
			w = tmp;
		}
		if(alfa > 90){
			alfa = 180 - alfa;
		}
		alfa = Math.PI*alfa/180;
		
		double beta = Math.atan(h/w);
	//	System.out.println("beta: "+ beta*180/Math.PI);
		if( alfa <= 2*beta){
			double p1 = getArea(beta, h);
			double p2 = 0;
			if(alfa < 2*beta){
				p2 = getArea(Math.PI/2 - beta, w);

			}
			area = h*w - 2*(p1 + p2);
//			System.out.println("p1 = " + p1 + "p2 = "+ p2);
		}else{
			area = h*h/Math.sin(alfa);
		}
	
		pw.print(area);
		pw.close();
	}





	private static double getArea(double angle, double len) {
			double r = Math.sqrt(h*h + w*w)/2;
			double hd = r*Math.sin(alfa+angle);
			double hm = hd - len/2;
			double a = hm/Math.sin(alfa);
			double b = a*Math.tan(alfa);
			return a*b/2;
	}


	
	
	static class Parser{
		
		StringTokenizer st;
		BufferedReader br;

		public Parser(InputStream is){
			this.br = new BufferedReader( new InputStreamReader(is));
			
		}
		
		public int nextInt(){
			return Integer.parseInt(nextToken());
		}
		
		public double nextDouble(){
			return Double.parseDouble(nextToken());
		}
		
		public String nextString(){
			return nextToken();
		}
		
		public int[] nextIntArray(int s){
			int[] a = new int[s];
			for(int i=0; i<s; ++i){
				a[i] = nextInt();
			}
			return a;
		}
		
		public int[][] nextIntTable(int r, int c){
			int[][] a = new int[r][c];
			for(int i=0; i<r; ++i){
				a[i] = nextIntArray(c);
			}
			return a;
		}
	
		private String nextToken() {
			if( st == null || ! st.hasMoreTokens() ){
				try{
					st = new StringTokenizer( br.readLine());
				}catch( Exception e){
					e.printStackTrace();
				}
			}
			return st.nextToken();
		}
		
	}
}