#include "Figure.h" class Triangle: public Figure { private: double x1, y1, x2, y2, x3, y3; template void init(T X1, T Y1, T X2, T Y2, T X3, T Y3) { x1 = double(X1); y1 = double(Y1); x2 = double(X2); y2 = double(Y2); x3 = double(X3); y3 = double(Y3); } public: template Triangle(T X1, T Y1, T X2, T Y2, T X3, T Y3) { init(X1, Y1, X2, Y2, X3, Y3); } Triangle(struct Point f, struct Point s, struct Point t); double calc_area(); double calc_perimiter(); void name(); };