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

// Cc code geometry
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 void solve(int testNumber, InputReader in, PrintWriter out) {
        double w = in.nextInt();
        double h = in.nextInt();
        if (w < h) {
            double t = w;
            w = h;
            h = t;
        }
        int alphaInt = in.nextInt();
        double res;
        if (alphaInt == 0 || alphaInt == 180) {
            res = h * w;
        } else if (alphaInt == 90) {
            res = h * h;
        } else {
            if (alphaInt > 90) alphaInt = 180 - alphaInt;
            double alpha = alphaInt / 180.0 * Math.PI;
            double diag = Math.sqrt(h * h + w * w);
            double a = Math.cos(alpha);
            double b = Math.sin(alpha);
            double c = w / 2 * a + h / 2 * b - w / 2;
            double r1 = c / a;
            double r2 = c / b;
            c = w / 2 * b + h / 2 * a - h / 2;
            double r3 = c / a;
            double r4 = c / b;
            if (r1 < 0 || r2 < 0 || r3 < 0 || r4 < 0) {
                res = h * h / Math.sin(alpha);
            } else {
                res = h * w - r1 * r2 - r3 * r4;
            }
        }
        out.printf("%.10f\n", res);
    }
}

class InputReader {
    public BufferedReader reader;
    public StringTokenizer tokenizer;

    public InputReader(InputStream stream) {
        reader = new BufferedReader(new InputStreamReader(stream));
        tokenizer = null;
    }

    public String next() {
        while (tokenizer == null || !tokenizer.hasMoreTokens()) {
            try {
                tokenizer = new StringTokenizer(reader.readLine());
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
        return tokenizer.nextToken();
    }

    public int nextInt() {
        return Integer.parseInt(next());
    }

    }