#include<string>
#include<iostream>
#include<cmath>
#include <iomanip>
using namespace std;
const double eps=1e-6;
#define Equal(a,b) ((fabs(a-b)<eps)?true:false)
struct P{
	double x,y,z;      //坐标
	double dx,dy,dz;   //方向
	bool isend;  //是否为端点
	int type; //0卡箍   1未确定分支点   2已确定分支点  3连接器
	int ref; //指向其代表的相应数据类型标号

	bool operator <(P B)const{
		if(!Equal(x,B.x))return x<B.x;
		if(!Equal(y,B.y))return y<B.y;
		if(!Equal(z,B.z))return z<B.z;
		return false;
	}
	bool operator ==(P B)const{
		return Equal(x,B.x)&&Equal(y,B.y)&&Equal(z,B.z);
	}
	bool operator !=(P B)const{
		return !(Equal(x,B.x)&&Equal(y,B.y)&&Equal(z,B.z));
	}

	void set(int i,double v){
		if(i==0)x=v;
		else if(i==1)y=v;
		else if(i==2)z=v;
	}
	const double get(int i){
		if(i==0)return x;
		else if(i==1)return y;
		else if(i==2)return z;

		return 0;
	}

	void reverse(){
		dx=-dx;
		dy=-dy;
		dz=-dz;
	}



	P(double x1,double y1,double z1){
		x=x1;y=y1;z=z1;
		dx=0;dy=dz=0;
		isend=0;
		type=ref=0;
	}
	P(){
		x=y=z=0;
		dx=0;dy=dz=0;
		isend=0;
		type=ref=0;
	}
	P operator -(P B)const{
		return P(x-B.x,y-B.y,z-B.z);
	}
	P operator +(P B)const{
		return P(x+B.x,y+B.y,z+B.z);
	}
	P operator *(double p)const{
		return P(x*p,y*p,z*p);
	}
	P operator /(double p)const{
		return P(x/p,y/p,z/p);
	}
	void print(string s){
		cout<<s<<setprecision(10)<<" : "<<x<<"  "<<y<<"  "<<z<<endl;
		return;
	}
	
	//设置方向
	void setDir(P& dir){
		dx=dir.x;
		dy=dir.y;
		dz=dir.z;
	}
}; 
P dirP(P &A){
	P B;
	B.x=A.dx;
	B.y=A.dy;
	B.z=A.dz;
	return B;
}