struct Inversion {
	Point o;//反演中心
	double r;//反演半径
	Inversion() {}
	Inversion(Point _o,double _r) {
		o=_o;
		r=_r;
	}
	//点的反演 flag为0获取失败 1获取成功
	void getPointInv(Point a,Point &aa,int &flag) {
		if(a==o) {
			flag=0;
			aa=a;
			return;
		}
		Point ptmp=a-o;
		double len=ptmp.len();
		ptmp=ptmp.trunc(r*r/len);
		aa=o+ptmp;
		flag=1;
	}
	//圆的反演 flag为1变成圆 -1变成直线
	void getCircleInv(circle c,Line &l,circle &cc,int &flag) {
		if(c.relation(o)^1) {
			Point p1,p2,pp1,pp2;
			Line lt;
			flag=1;
			if(c.p==o) {
				cc.p=o;
				cc.r=r*r/c.r;
				return;
			}
			lt=Line(c.p,o);
			int ii=c.pointcrossline(lt,p1,p2);
			int f;
			getPointInv(p1,pp1,f);
			getPointInv(p2,pp2,f);
			Point pp=(pp1+pp2)/2;
			cc.p=pp;
			cc.r=pp1.distance(pp2)/2;
			return;
		}
		flag=-1;
		Point ptmp=c.p*2-o,pptmp,p1,p2;
		int f;
		getPointInv(ptmp,pptmp,f);
		p1=o-pptmp;
		p1=p1.rotleft();
		p1=p1+pptmp;
		l=Line(pptmp,p1);
	}
	//直线的反演 成圆
	void getLineInv(Line L,circle &cc,int &flag) {
		if(L.relation(o)==3) {
			flag=0;
			return;
		}
		flag=1;
		Point p=L.lineprog(o),ans;
		int f;
		getPointInv(p,ans,f);
		cc.r=ans.distance(o)/2;
		cc.p=(ans+o)/2;
	}
} iv;