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 static java.lang.Math.PI;
import static java.lang.Math.abs;
import static java.lang.Math.acos;
import static java.lang.Math.cos;
import static java.lang.Math.min;
import static java.lang.Math.sin;
import static java.lang.Math.sqrt;
import static java.lang.System.in;
import static java.lang.System.out;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Comparator;
import java.util.Scanner;

public class A280 {
	public static Scanner sc = new Scanner(in);
	StringBuilder sb = new StringBuilder();
	BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

	public void run() throws IOException {
		String input;
		String[] inputArray;
		input = br.readLine();
		inputArray = input.split(" ");

		double w = Integer.valueOf(inputArray[0]);
		double h = Integer.valueOf(inputArray[1]);
		double alpha = Integer.valueOf(inputArray[2]);
		if (alpha>90) alpha = 180-alpha;
		alpha *=Math.PI/180;
		if (h>w) {
			double temp=w;
			w=h; 
			h=temp;
		}
		P [] t = new P[4], rt = new P[4];
		t[0] = new P(-w/2,-h/2);
		t[1] = new P(w/2,-h/2);
		t[2] = new P(w/2,h/2);
		t[3] = new P(-w/2,h/2);
		for (int i=0; i<4; i++) {
			rt[i]=t[i];
			rt[i]=rt[i].rotate(P.O, alpha);
		}
		double ans = w*h;
		if (Math.tan(alpha/2) <h/w){
			P A = S.intersection(new S(t[1],t[2]), new S(rt[0], rt[1]));
			P B = S.intersection(new S(t[1],t[2]), new S(rt[1], rt[2]));
			P C = S.intersection(new S(t[2],t[3]), new S(rt[1], rt[2]));
			P D = S.intersection(new S(t[2],t[3]), new S(rt[2], rt[3]));
			double area = D.dist(rt[2])*C.dist(rt[2]) + B.dist(rt[1])*A.dist(rt[1]);
			ans-=area;
		} else{
			P A = S.intersection(new S(t[2],t[3]), new S(rt[0], rt[1]));
			P B = S.intersection(new S(t[2],t[3]), new S(rt[2], rt[3]));
			double area = (B.dist(rt[2]) + A.dist(rt[1]))*h;
			ans-=area;
		}
		ln(ans);
	
	
	}

	public static void main(String[] args) throws IOException {
		new A280().run();
	}
	public static void ln(Object obj) {
		out.println(obj);
	}
	static class P{
		
			static final double EPS=1e-10;
			static int signum(double x){
				return x<-EPS?-1:x>EPS?1:0;
			}
		static Comparator<P> comp=new Comparator<P>(){
			public int compare(P p1, P p2) {
				return signum(p1.x-p2.x)!=0?signum(p1.x-p2.x):signum(p1.y-p2.y);
			}
		};
		public static  final P O=new P(0,0);
		final double x,y;
		P(double _x,double _y){
			x=_x;y=_y;
		}
		
		P add(P a){
			return new P(x+a.x,y+a.y);
		}
		P sub(P a){
			return new P(x-a.x,y-a.y);
		}
		P mul(P a){
			return new P(x*a.x-y*a.y,x*a.y+y*a.x);
		}
		P div(P a){
			double d2=a.dist2(O);
			return new P(dot(a,this)/d2,cross(a,this)/d2);
		}
		
		P conj(){
			return new P(x,-y);
		}
		
		static double dot(P a,P b){
			return  a.x*b.x+a.y*b.y;
		}
		
		static double cross(P a,P b){
			return  a.x*b.y-a.y*b.x;
		}
		
		double dist2(P p){
			return (x-p.x)*(x-p.x)+(y-p.y)*(y-p.y);
		}
		
		double dist(P p){
			return sqrt(dist2(p));
		}
		public double norm(){
			return dist(O);
		}
		
		static int ccw(P a,P b,P c){
			b=b.sub(a);c=c.sub(a);
			if(cross(b,c)>EPS)return 1;
			if(cross(b,c)<-EPS)return -1;
			if(dot(b,c)<-EPS)return 2;
			if(b.norm()<c.norm()-EPS)return -2;
			return 0;
		}
		
		
		
		static double arg(P o,P a){
			P dir=a.sub(o);
			double s=acos(dir.x/dir.norm());
			return dir.y>=0?s:2*PI-s;
		}
		
		static double arg(P a,P b, P c){
			double angleA = P.arg(a,b);
			double angleB = P.arg(b,c);
			double angle =  Math.PI+angleA-angleB;
			if (angle-2*Math.PI>EPS) angle-=2*Math.PI;
			if (angle<EPS) angle+=2*Math.PI;
			return angle;
		}
		
		P rotate(P o,double arg){
			return o.add(this.sub(o).mul(new P(cos(arg),sin(arg))));
		}
		
		static double S2(P a,P b,P o){
			return cross(a.sub(o),b.sub(o));
		}
		static double S(P a,P b,P o){
			return S2(a,b,o)/2;
		}
		
		static P polar(double abs,double arg){
			return new P(abs*cos(arg),abs*sin(arg));
		}
		
		static P proj(P p,P o){
			return o.mul(new P(dot(p,o)/o.norm(),0));
		}
		public boolean equals(Object obj) {
			if(obj instanceof P){
				P p=(P)obj;
				return signum(x-p.x)==0 && signum(y-p.y)==0;
			}
			return false;
		}
		public String toString(){
			return "("+x+","+y+")";
		}
	}
	static class L extends AL{
		L(P _p1, P _p2) {super(_p1, _p2);}

		
		double dist(P p){
			return abs(P.S(p2,p,p1))/p1.sub(p2).norm();
		}
		boolean isIntersect(P p){
			return abs(P.S(p2,p,p1))<EPS;
		}
		boolean isIntersect(L l){
			if(isPoint() && l.isPoint())return p1.equals(l.p1);
			if(isPoint())return l.isIntersect(p1);
			if(l.isPoint())return isIntersect(l.p1);
			return !isParallel(l) || isIntersect(l.p1);
		}

		
		static P FootOfLP(L l,P p){
			return l.p1.add(P.proj(p.sub(l.p1),l.p2.sub(l.p1)));
		}

		
		static P LineSymmetricLP(L l,P p){
			return FootOfLP(l,p).mul(new P(2.0,0)).sub(p);
		}

		public boolean equals(Object obj) {
			if(obj instanceof L){
				L l=(L)obj;
				return isParallel(l) && isIntersect(l.p1);
			}
			return false;
		}
	}
	
	class S extends AL{
		S(P _p1, P _p2) {super(_p1, _p2);}
		boolean isIntersect(P p){
			return p1.sub(p).norm()+p2.sub(p).norm()<=p1.sub(p2).norm()+EPS;
		}
		boolean isIntersect(L l){
			return P.cross(l.p2.sub(l.p1),p1.sub(l.p1))*
				P.cross(l.p2.sub(l.p1),p2.sub(l.p1))<EPS;
		}
		boolean isIntersect(S l){
			return P.ccw(p1,p2,l.p1)*P.ccw(p1,p2,l.p2)<=0
			&& P.ccw(l.p1,l.p2,p1)*P.ccw(l.p1,l.p2,p2)<=0;
		}
		
		double dist(P p){
			if(P.dot(p2.sub(p1),p.sub(p1))<EPS)return p.sub(p1).norm();
			if(P.dot(p1.sub(p2),p.sub(p2))<EPS)return p.sub(p2).norm();
			return abs(P.S(p2,p,p1))/p1.sub(p2).norm();
		}
		
		double dist(L l){
			if(isIntersect(l))return 0;
			return min(l.dist(p1),l.dist(p2));
		}
		
		double dist(S l){
			if(isIntersect(l))return 0;
			return min(min(dist(l.p1),dist(l.p2)),min(l.dist(p1),l.dist(p2)));
		}
	}
	static abstract class AL{
		
			static final double EPS=1e-10;
			static int signum(double x){
				return x<-EPS?-1:x>EPS?1:0;
			}
		public P p1,p2;
		AL(P _p1,P _p2){
			p1=_p1;
			p2=_p2;
		}

		boolean isPoint(){
			return p1.equals(p2);
		}









		
		boolean isParallel(AL l){
			return abs(P.cross(p2.sub(p1),l.p2.sub(l.p1)))<EPS;
		}
		
		boolean isOrthogonal(AL l){
			return abs(P.dot(p2.sub(p1),l.p2.sub(l.p1)))<EPS;
		}

		
		static P intersection(AL l1,AL l2){
			P dl1=l1.p2.sub(l1.p1),dl2=l2.p2.sub(l2.p1);
			double a=P.cross(dl2,l2.p1.sub(l1.p1));
			double b=P.cross(dl2,dl1);
			if(abs(a)<EPS && abs(b) <EPS)return l1.p1;
			return l1.p1.add(dl1.mul(new P(a/b,0.0)));
		}


		public boolean equals(Object obj) {
			if(obj instanceof L){
				L l=(L)obj;
				return this.p1.equals(l.p1) && this.p2.equals(l.p2);
			}
			return false;
		}
		public String toString(){
			return p1+"-"+p2;
		}
	}
}