maze_illusion的博客

//符号判断int sgn( double x ){ if ( fabs(x)<eps ) return 0; if ( x<0 ) return -1; if ( x>0 ) return 1;}//点类定义struct Point{ double x,y; Point(){} Point( double _x ,...

const double eps = 1e-8;const double pi = acos(-1);int sgn( double x ){ if ( fabs(x)<eps ) return 0; if ( x<0 ) return -1; if ( x>0 ) return 1;}struct point{ double x...

1.以整点为顶点的线段，覆盖的点的个数为GCD(dx,dy)2.Pick公式：顶点坐标均是整点的简单多边形：面积=内部格点数+边上格点数/2-13.任意一个多边形的面积等于按顺序求相邻两个点与原点组成的向量的叉积之和...

//凸包，Andrew算法//点编号1~n//返回凸包结果Stack[1~Top]Point List[maxn<<1],Stack[maxn<<1]; int Top;bool cmp( Point a , Point b ){ if ( a.x==b.x ) return a.y<b.y; else return a.x<b.x;...

const double eps = 1e-8;const double pi = acos(-1.0);//判浮点数符号int sgn( double x ){ if ( fabs(x)<eps ) return 0; if ( x<0 ) return -1; if ( x>0 ) return 1;}//Point定义struct ...

1.以格子点为顶点的线段，覆盖的点的个数为GCD(dx,dy)2.Pick公式：顶点坐标均是整点的简单多边形：面积=内部格点数目+边上格点数目/2-13.任意一个多边形的面积等于按顺序求相邻两个点与原点组成的向量的叉积之和三点求圆心坐标（三角形外心）//三点求圆心坐标（三角形外心）Point waixin( Point a , Point b , Point c ){ d...

一般套路：对散点跑一个凸包出来，然后在凸包上进行旋转卡壳。例如：（旋转卡壳求两凸包最小距离完整代码）#include<map>#include<set>#include<ctime>#include<stack>#include<cmath>#include<queue>#include<vecto...

//凸包，Graham算法//点编号0~n-1//返回凸包结果Stack[0~Top-1]Point List[maxn],Stack[maxn]; int Top;bool cmp( Point a , Point b ){ double tmp = (a-List[0])^(b-List[0]); if ( tmp>0 ) return true; e...

初始要先按x升序y升序排个序struct Point{ double x,y; Point(){} Point( double _x , double _y ) { x = _x; y = _y; } Point operator -( const Point&b )const { retur...

int sgn( double x ){ if ( fabs(x)<eps ) return 0; if ( x<0 ) return -1; if ( x>0 ) return 1;}struct Point{ double x,y; Point(){} Point( double _x , double _y ) ...

向左移动（对应逆时针）：//求两点距离double dist( Point a , Point b ){ return sqrt( (a-b)*(a-b) );}//将线段ab往左移动距离rvoid change( Point a , Point b , Point &c , Point &d , double r ){ double dis = ...

bool norm_Inter( Line l1 , Line l2 ){ double c1 = (l1.e-l1.s)^(l2.s-l1.s); double c2 = (l1.e-l1.s)^(l2.e-l1.s); double c3 = (l2.e-l2.s)^(l1.s-l2.s); double c4 = (l2.e-l2.s)^(l1.e-l2....