计算几何模板存储

#include<cstdio>
#include<cmath>
#include<algorithm>
using namespace std;
const double eps=1e-10;
int dcmp(double x){
    if(fabs(x)<eps)return 0;
    else return x<0?-1:1;
}//精度
struct Point{
    double x,y;
    Point(double x=0,double y=0):x(x),y(y){ };
};//定义点
typedef Point Vector;//定义向量
//定义向量基本计算运算符
Vector operator + (Point A,Point B){
    return Vector(A.x+B.x,A.y+B.y);
}//定义向量加符合三角形定则
Vector operator - (Point A,Point B){
    return Vector(A.x-B.x,A.y-B.y);
}//定义向量减符合三角形定则
Vector operator * (Vector A,double p){
    return Vector(A.x*p,A.y*p);
}//定义向量数乘
Vector operator / (Vector A,double p){
    return Vector(A.x/p,A.y/p);
}//定义向量数除
//定义向量比较运算符
bool operator < (const Point& a,const Point& b){
    return  a.x<b.x||(a.x==b.x&&a.y<b.y);
}//定义向量比较这里优先比较x维
bool operator > (const Point& a,const Point& b){
    return a.x>b.x||(a.x==b.x&&a.y>b.y);
}//定义向量比较这里优先比较x维
bool operator == (const Point& a,const Point& b){
    return dcmp(a.x-b.x)==0&&dcmp(a.y-b.y)==0;
}//定义向量相等为完全相同
//向量点积相关
double Dot(Vector A,Vector B){
    return A.x*B.x+A.y*B.y;
}//计算向量点积
double Lenth(Vector A){
    return sqrt(Dot(A,A));
}//计算向量长
double Angle(Vector A,Vector B){
    return acos(Dot(A,B)/Lenth(A)/Lenth(B));
}//计算向量夹角（有序的） 
//向量叉积相关
double Cross(Vector A,Vector B){
    return A.x*B.y-A.y*B.x;
}//计算向量叉积
double Area(Point A,Point B,Point C){
    return fabs(Cross(B-A,C-A)/2);
}//计算abc三点三角形的数值面积
int main()
{
    return 0;
}