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.util.*;
import java.io.*;

public class Main implements Runnable {
    BufferedReader in;
    PrintWriter out;
    StringTokenizer stok;

    String nextToken() {
        while (stok == null || !stok.hasMoreTokens()) {
            try {
                stok = new StringTokenizer(in.readLine());
            } catch (Exception e) {
                return null;
            }
        }
        return stok.nextToken();
    }

    int nextInt() {
        return Integer.parseInt(nextToken());
    }

    long nextLong() {
        return Long.parseLong(nextToken());
    }

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

    // File names!!!

    class Point {
        double x, y;

        Point(double x, double y) {
            this.x = x;
            this.y = y;
        }
    }

    Point rotate(Point p, double alph) {
        double r = Math.sqrt(p.x * p.x + p.y * p.y);
        double phi = Math.atan2(p.y,p.x);
        return new Point(r * Math.cos(phi + alph), r * Math.sin(phi + alph));
    }

    double square3(double x1, double y1, double x2, double y2) {
        return 0.5 * (x1 * y2 - x2 * y1);
    }

    double square(Point a, Point b, Point c) {
        return Math.abs(square3(b.x - a.x, b.y - a.y, c.x - a.x, c.y - a.y));
    }

    double dist(Point a, Point b) {
        return Math.sqrt((a.x - b.x) * (a.x - b.x) + (a.y - b.y) * (a.y - b.y));
    }

    void solve() throws IOException {
        double a = nextDouble();
        double b = nextDouble();
        double alph = nextDouble();
        if (a < b) {
            double _ = a;
            a = b;
            b = _;
            alph = 180 - alph;
        }
        if (alph == 0 || alph == 180) {
            out.printf("%.9f", a * b);
            return;
        }
        if (alph > 90) {
            alph = 180 - alph;
        }

        alph *= Math.PI / 180;

        Point A, B, C, D;
        A = new Point(a / 2, b / 2);
        B = new Point(a / 2, -b / 2);
        C = new Point(-a / 2, -b / 2);
        D = new Point(-a / 2, b / 2);

        Point A1, B1, C1, D1;
        A1 = rotate(A, alph);
        B1 = rotate(B, alph);
        C1 = rotate(C, alph);
        D1 = rotate(D, alph);

        double ans = a * b;

        if (B1.y < A.y) {
            Point H = new Point(A1.x, A.y);
            Point I1 = new Point(H.x - (A1.y - H.y) / Math.tan(alph), H.y);
            Point I2 = new Point(H.x + (A1.y - H.y) / Math.tan(Math.PI / 2.0 - alph), H.y);
            double k = dist(I2, A) / dist(A1, I2);
            double sq = square(A1, I1, I2);
            ans = a * b - 2.0 * sq - 2.0 * sq * k * k;
        } else {
            Point H1 = new Point(A1.x, A.y);
            Point H2 = new Point(B1.x, A.y);
            Point I1 = new Point(H1.x - (A1.y - H1.y) / Math.tan(alph), H1.y);
            Point I2 = new Point(H2.x - (B1.y - H1.y) / Math.tan(alph), H2.y);
            double sq1 = square(A1, I1, B1);
            double sq2 = square(B1, I1, I2);
            ans = a * b - 2.0 * (sq1 + sq2);
        }

        out.printf("%.9f", ans);
    }

    public void run() {
        try {
            in = new BufferedReader(new InputStreamReader(System.in));
            out = new PrintWriter(System.out);
            solve();
            out.close();
            in.close();
        } catch (Exception e) {
            e.printStackTrace();
            System.exit(1);
        }
    }

    public static void main(String[] args) {
        try {
            Locale.setDefault(Locale.US);
        } catch (Exception ignore) {
        }
        new Thread(new Main()).start();
    }
}