题意
分析
就按题意模拟即可,注意到对称性,只需要知道如何求其中一个。
注意A、B、C按逆时针排列,利用这个性质可以避免旋转时分类讨论。
时间复杂度\(O(T)\)
代码
#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<cmath>
#include<set>
#include<map>
#include<queue>
#include<stack>
#include<algorithm>
#include<bitset>
#include<cassert>
#include<ctime>
#include<cstring>
#define rg register
#define il inline
#define co const
template<class T>il T read()
{
rg T data=0;
rg int w=1;
rg char ch=getchar();
while(!isdigit(ch))
{
if(ch=='-')
w=-1;
ch=getchar();
}
while(isdigit(ch))
{
data=data*10+ch-'0';
ch=getchar();
}
return data*w;
}
template<class T>T read(T&x)
{
return x=read<T>();
}
using namespace std;
typedef long long ll;
co double eps=1e-10;
int dcmp(double x)
{
if(fabs(x)<eps)
return 0;
else
return x<0?-1:1;
}
struct Point
{
double x,y;
Point(double x=0,double y=0)
:x(x),y(y){}
bool operator<(co Point&rhs)co
{
return x<rhs.x||(x==rhs.x&&y<rhs.y);
}
bool operator==(co Point&rhs)co
{
return dcmp(x-rhs.x)==0&&dcmp(y-rhs.y)==0;
}
};
typedef Point Vector;
Vector operator+(Vector A,Vector B)
{
return Vector(A.x+B.x,A.y+B.y);
}
Vector operator-(Point A,Point B)
{
return Vector(A.x-B.x,A.y-B.y);
}
Vector operator*(Vector A,double p)
{
return Vector(A.x*p,A.y*p);
}
Vector operator/(Vector A,double p)
{
return Vector(A.x/p,A.y/p);
}
double Dot(Vector A,Vector B)
{
return A.x*B.x+A.y*B.y;
}
double Length(Vector A)
{
return sqrt(Dot(A,A));
}
double Angle(Vector A,Vector B)
{
return acos(Dot(A,B)/Length(A)/Length(B));
}
double Cross(Vector A,Vector B)
{
return A.x*B.y-A.y*B.x;
}
double Area2(Point A,Point B,Point C)
{
return Cross(B-A,C-A);
}
Vector Rotate(Vector A,double rad)
{
return Vector(A.x*cos(rad)-A.y*sin(rad),A.x*sin(rad)+A.y*cos(rad));
}
Vector Normal(Vector A)
{
double L=Length(A);
return Vector(-A.y/L,A.x/L);
}
Point GetLineIntersection(Point P,Vector v,Point Q,Vector w)
{
Vector u=P-Q;
double t=Cross(w,u)/Cross(v,w);
return P+v*t;
}
double DistanceToLine(Point P,Point A,Point B)
{
Vector v1=B-A,v2=P-A;
return fabs(Cross(v1,v2))/Length(v1);
}
double DistanceToSegment(Point P,Point A,Point B)
{
if(A==B)
return Length(P-A);
Vector v1=B-A,v2=P-A,v3=P-B;
if(dcmp(Dot(v1,v2))<0)
return Length(v2);
if(dcmp(Dot(v1,v3))>0)
return Length(v3);
return DistanceToLine(P,A,B);
}
Point GetLineProjection(Point P,Point A,Point B)
{
Vector v=B-A;
return A+v*(Dot(v,P-A)/Dot(v,v));
}
bool SegmentProperIntersection(Point a1,Point a2,Point b1,Point b2)
{
double c1=Cross(a2-a1,b1-a1),c2=Cross(a2-a1,b2-a1),
c3=Cross(b2-b1,a1-b1),c4=Cross(b2-b1,a2-b1);
return dcmp(c1)*dcmp(c2)<0&&dcmp(c3)*dcmp(c4)<0;
}
bool OnSegment(Point p,Point a1,Point a2)
{
return dcmp(Cross(a1-p,a2-p))==0&&dcmp(Dot(a1-p,a2-p))<0;
}
double PolygonArea(Point*p,int n)
{
double area=0;
for(int i=1;i<n-1;++i)
area+=Cross(p[i]-p[0],p[i+1]-p[0]);
return area/2;
}
Point getD(Point A,Point B,Point C)
{
Vector v1=C-B;
double a1=Angle(A-B,v1);
v1=Rotate(v1,a1/3);
Vector v2=B-C;
double a2=Angle(A-C,v2);
v2=Rotate(v2,-a2/3);
return GetLineIntersection(B,v1,C,v2);
}
//Point read()
//{
// Point p;
// scanf("%lf %lf",&p.x,&p.y);
// return p;
//}
int main()
{
// freopen(".in","r",stdin);
// freopen(".out","w",stdout);
int T;
scanf("%d",&T);
Point A,B,C,D,E,F;
while(T--)
{
// read(A);read(B);read(C);
scanf("%lf %lf %lf %lf %lf %lf",&A.x,&A.y,&B.x,&B.y,&C.x,&C.y);
// cerr<<"A="<<A.x<<" "<<A.y<<endl;
// cerr<<"B="<<B.x<<" "<<B.y<<endl;
// cerr<<"C="<<C.x<<" "<<C.y<<endl;
D=getD(A,B,C);
E=getD(B,C,A);
F=getD(C,A,B);
printf("%lf %lf %lf %lf %lf %lf\n",D.x,D.y,E.x,E.y,F.x,F.y);
}
return 0;
}
Hint
注意向量的读入。开始想重载一个read
结果是错的,迫不得已改成直接scanf
。
以后可以在结构体里面实现一个read
。
UVA11178 Morley's Theorem
原文地址:https://www.cnblogs.com/autoint/p/10125282.html
时间: 2024-10-09 13:34:16