vectors c++.. help with codes. :)

i then have came up with these codes(below) that has some sort of errors and yet to be incomplete with what the problem is asking..to all the great out there whom i admire.. pls help me debug and complete my codes..
here's the code:

Code:

#include <cstdlib>
#include <iostream>
#include<fstream>
#include<vector>
#include<string>
using namespace std;
class Student{
    private:
            double grade;
    public:
      char fullName();
      char idNumber();
      char subjectName();
      double classStanding(){return grade;};
      double prelimExam(){return grade;};
      double midtermExam(){return grade;}
      double prefinalExam(){return grade;}
      double finalExam(){return grade;};
bool set(double g){
     if( ( g > 0.0 )&&( g < 100.0 ) )
     {
           grade = g;                
                           
                      return true;     
                      }
     
     else
     {
         cout<<"Alert: There is an invalid grade for this particular student.";
         return false;
         }
     }
      
      
      
      };



int main(int argc, char *argv[])
{
    
    ifstream fin;
fin.open("students.in");
string line;
    while(getline(fin,line)){
                             
                   for(int i = 0; i < line.length() ; i++){
                           
                           
                            }           
                             
                             
                             
                             }
                             ofstream fout;
                             fout.open("students.out");
                             
    system("PAUSE");
    return EXIT_SUCCESS;
}

The problem is attached ... so just clck the link to view the problem.