//student. h
#include<string>
using namespace std;
class student
{
public:
    void display();
private:
    int num;
    string name;
    char sex;
};
//student. cpp
#include<iostream>
#include"student.h"
void student::display()
{cout<<"num:"<<num<<endl;
cout<<"name:"<<name<<endl;
cout<<"sex:"<<sex<<endl;
}
//main.cpp
#include<iostream>
#include"student.h"
using namespace std;
int main()
{
    student stud;
    stud display();
    return 0;
}

就是student.h头文件不知怎么弄？