类中 嵌套调用

#include <stdio.h>
#include <string.h>
#include <iostream>
using namespace std;
#define N 5
 
class student
{ public:
  char num[16];
  char name[8];
  int  score[4];
  
void input( );
void input(char nu[],char na[],int a[] );
  void print( );

};

class Grade
{
public:
       // void Add();
       // void Erase();
      //  void Change();
       // void Search();
       // void Sort();            //总分排序
      //  void GetHigh();            //最高分
      //  void GetLow();            //最低分
      //  void GetAverage();        //平均分
      //  void List();
void input( );
void print( );
private:
        student s[100];    //学生
        int number;        //已经输入成绩的学生人数
};



void Grade::input( )
{
     int j,flag=1;
     number=1;
     while(flag)
     {
        cout<<"please enter student num:";
            cin>>s[number].num;
        cout<<"please enter student name:";
            cin>>s[number].name;
       for(j=0;j<4;j++)
       {
           cout<<"please enter student score:";
           cin>>s[number].score[j] ;
       }
        number++;
        cout<<"if input again,enter 1,else enter 0:";
        cin>>flag;
     }
}

void Grade::print( )
{
     int i,j;
     for(i=1;i<number;i++)
     {
        cout<<"-------------------------------------------------\n";
        cout<<"\n学号   姓名    成绩1   成绩2  成绩3   成绩4\n";
        cout<<"-------------------------------------------------\n";
        cout<<s[number].num<<"   "<<s[number].name<<"      ";
        for(j=0;j<4;j++)
        cout<<s[number].score[j] <<"     ";
        cout<<"\n-----------------------------------------------\n";
     }
}

 
void main()
{
       Grade rjgcbd2016;
       rjgcbd2016.input( );
       rjgcbd2016.print( );
}





在grade 类中创建student类 存储数据  但是不知道怎么调用  或者存储的有问题

求解