11 2021 档案

摘要：#include<iostream> #include<typeinfo> class Graph { public: virtual void draw(){std::cout<<"Graph::draw():just as an interface\n";} }; class Rectangle 阅读全文

摘要：#include<iostream> using namespace std; class vector_int { public: vector_int(); vector_int(int s); vector_int(int s,int x); void print(); int &at(int 阅读全文