自定义头文件

#include <iostream>  //这是标准的头文件，用<>#include <string>#include "demo2.h"   //#include 是预处理器指令，#include "Dog.h"    //这是自己写的头文件用"".using std::cout;using std::string;int main (){string name;cout << "xiao\n";std::cout << "xiao ! " << std::endl;return 0;}