UVA 11178 Morley定理 二维几何问题

UVA 11178 Morley定理

Morley定理：作三角形ABC每个内角的三等分线，相交成三角形DEF，则DEF是等边三角形。

输入T样例数，之后输入一行6个整数XA，YA，XB，YB，XC，YC；

输出六个实数XD,YD,XE,YE,XF,YF;

解题思路：

1，这题就是调用我们之前准备模版里面的函数就能实现

2，这种题能加深对模版的理解程度

#include<iostream>#include<cstdio>#include<cstring>#include<cmath>using namespace std;struct Point{    double x,y ;    Point(double x=0,double y=0):x(x),y(y){}};typedef Point Vector ;double Dot(Vector A,Vector B){return A.x*B.x + A.y*B.y ;}double Length(Vector A){return sqrt(Dot(A,A));}Vector operator - (Point A,Point B){return Vector(A.x-B.x,A.y-B.y);}Vector operator + (Vector A,Vector 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);}double Angle(Vector A,Vector B){return acos(Dot(A,B)/Length(A)/Length(B)) ;}Vector Rotate(Vector A,double rad){return Vector(A.x*cos(rad)-A.y*sin(rad),A.x*sin(rad)+A.y*cos(rad));}double Cross(Vector A,Vector B){return A.x*B.y - A.y*B.x ;}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 ;}Point read_Point(){    double x,y ;    scanf("%lf%lf",&x,&y);    return Point(x,y) ;}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);}int main(){    int T ;    Point A,B,C,D,E,F ;    scanf("%d",&T);    while(T--){        A = read_Point() ;        B = read_Point() ;        C = read_Point() ;        D = getD(A,B,C) ;        E = getD(B,C,A) ;        F = getD(C,A,B) ;        printf("%.6lf %.6lf %.6lf %.6lf %.6lf %.6lf\n",D.x,D.y,E.x,E.y,F.x,F.y);    }    return 0;}