题意:求Morley定理的3个点的坐标。
题目链接:http://acm.hust.edu.cn/vjudge/problem/viewProblem.action?id=18543
——>>照要求做~
#include <cstdio> #include <cmath> using namespace std; struct Point{ double x; double y; Point(double x = 0, double y = 0):x(x), y(y){} }p[3]; typedef Point Vector; Vector operator + (Point A, Point 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 * (Point A, double p){ return Vector(A.x * p, A.y * p); } Vector operator / (Point 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 Cross(Vector A, Vector B){ return A.x * B.y - B.x * A.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)); } 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; } void read(){ for(int i = 0; i < 3; i++) scanf("%lf%lf", &p[i].x, &p[i].y); } Point getD(Point A, Point B, Point C){ Vector BC = C - B, BA = A - B; Vector CB = B - C, CA = A - C; BC = Rotate(BC, Angle(BC, BA) / 3); CB = Rotate(CB, -Angle(CB, CA) / 3); return GetLineIntersection(B, BC, C, CB); } void solve(){ Point D, E, F; D = getD(p[0], p[1], p[2]); E = getD(p[1], p[2], p[0]); F = getD(p[2], p[0], p[1]); printf("%.6f %.6f %.6f %.6f %.6f %.6f\n", D.x, D.y, E.x, E.y, F.x, F.y); } int main() { int N; scanf("%d", &N); while(N--){ read(); solve(); } return 0; }