classes and objects

The source code for program that can check if a numbers prime is given below, copy it in note pad and save it as “.cpp”. Then use suitable compiler to compile it.

/*
 *      
 *      Copyright 2011 techstream.org < techstream.org[at]gmail.com >
 *      
 *      This program is free software; you can redistribute it and/or modify
 *      it under the terms of the GNU General Public License as published by
 *      the Free Software Foundation; either version 2 of the License, or
 *      (at your option) any later version.
 *      
 *      This program is distributed in the hope that it will be useful,
 *      but WITHOUT ANY WARRANTY; without even the implied warranty of
 *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *      GNU General Public License for more details.
 *      
 */

#include
#include      // to use clrscr and getch
class stud {
		int rno;
		float mark[5],total,percent;
		char name[20];
		void calcpercent()
		{
		   percent=(total*100)/500;
		}
       public:
		void getdata();
		void output();
	   };
	   void stud::getdata()
	   {
       
		total=0;
		clrscr();
		cout<<"enter roll no: ";
		cin>>rno;
		cout<<"enter name: ";
		cin>>name;
		cout<<"enter marks:n ";
		for(int i=0;i<5;i++)
		 {
			cout<<"enter mark in subject"<>mark[i];
			total=total+mark[i];
		 }
		     calcpercent();
		  }
		  void stud::output()
		  {
		    clrscr();
		cout<<"n roll number :"<