#include <string> #include <iostream> #include <assert.h> using std::string; using std::cout; using std::endl; class Subject{ public:     virtual string Name() = 0; }; class Calculus :public Subject { public:     string Name(){         return "Calculus"; //微积分     } }; class English :public Subject { public:     string Name(){         return "English";     } }; class Algebra :public Subject { public:     string Name(){         return "Algebra"; //代数     } }; class Cpp :public Subject { public:     string Name(){         return "C++ Language";     } }; class Physics :public Subject { public:     string Name(){         return "Physics";     } }; void fillObjects(Subject* o[]) {     //fill Calculus, English, Algebra, C++ Language, Physics     o[0] = new Calculus;     o[1] = new English;     o[2] = new Algebra;     o[3] = new Cpp;     o[4] = new Physics; } int main() {     Subject* o[5];     fillObjects(o);     assert(o[0]->Name() == "Calculus");     assert(o[1]->Name() == "English");     assert(o[2]->Name() == "Algebra");     assert(o[3]->Name() == "C++ Language");     assert(o[4]->Name() == "Physics");     cout << "pass!!!" << endl;     for (int i = 0;i < 5;i++)         delete o[i];     return 0; }