UVA - 11178 Morley's Theorem(几何，蓝书)

Myth丶恋晨 2022-05-27 08:16 131阅读 0赞

#include<cstdio>
    #include<cmath>
    using namespace std;
    
    struct Point {
    	double x, y;
    	Point (double x=0, double y=0):x(x), y(y){}
    };
    
    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); }
    
    Point read_point(){
    	Point p;
    	scanf("%lf%lf", &p.x, &p.y);
    	return 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));
    }
    
    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 v1, Vector v2){
    	return v1.x*v2.y-v1.y*v2.x;
    }
    
    Point GetLineIntersection(Point A, Vector v1, Point B, Vector v2){
    	Vector v3=A-B;
    	double t=Cross(v2, v3)/Cross(v1, v2);
    	return A+v1*t;
    }
    
    Point getP(Point A, Point B, Point C){
    	Vector v1=B-A;
    	double a1=Angle(v1, C-A);
    	v1=Rotate(v1, a1/3);
    	
    	Vector v2=A-B;
    	double a2=Angle(v2, C-B);
    	v2=Rotate(v2, -a2/3);
    	
    	return GetLineIntersection(A, v1, B, v2);
    	
    }
    
    int main(){
    	int T;
    	scanf("%d", &T);
    	
    	while(T--){
    		Point A, B, C, D, E, F;
    		A=read_point();
    		B=read_point();
    		C=read_point();
    		
    		D=getP(B, C, A);
    		E=getP(C, A, B);
    		F=getP(A, B, C);
    		printf("%.6lf %.6lf %.6lf %.6lf %.6lf %.6lf\n", D.x, D.y, E.x, E.y, F.x, F.y);
    	}		
    	
    	return 0;
    }