HI I VE BEEN TRYING TO GET OUTPUT FOR THIS PROGRAM BUT ITS SHOWING SOME ERROR REGARDING HEADER FILES.
I JUS NEED UR GELP IN CORRECTING THE PROGRAM

HERES THE SOURCE CODE ;-

Code:
//RENT A CAR PROJECT
#include <iostream.h>
#include<fstream.h>
#include<stdio.h>
#include<conio.h>
#include<string.h>
#include<iomanip.h>
#include<dos.h>
#include <stdlib.h>
#include <limits.h>

class Car
{
	private:
		unsigned long s_no;
		char strName[25];
		int nDays;
		char strType;
		char strCompany[10] ;
		int nAge;
		char strDesig[10],strPIan;
		int nCost; 
		int ndln;
		int nPhone;
		char strWeekEnd;
		char strSex;
		int nBox;
		int nPlan;

	public:
		unsigned long_get( );
		void GetDetails( );
		void Individual( );
		void Status( );
		void Company( ); 
		void AddDetails( );
		void ShowDetails( );
		void ShowObject( );
		void DeleteObject( );
		void Modify( );
	//	void Reports( );
		void Search( );
};
Car cars;

void Car::GetDetails( )
{
	char choice;
	char use;


		cout<<"Select Car Type\n";
		cout<<"Economy .... .A\n";
		cout<<"Luxury ......... B\n";
		cout<<"4 x 4 .......... .C\n";
		cout<<"Exit ............ ";
		cin>>choice;

		if((choice=='A')||(choice=='B')||(choice=='C'))
		{
			cout<<"please enter \n P for personal use or \n";
			cout<<"C for company use";
			cin>>use;
			if(use=='P')
				Individual();
			else if (use=='C')
			 Company();

		}
		else
			cout<<"wrong option "; 
}

void Car::Individual()
{
 
	system ("CLS");
	cout<<"enter the customer name\n";
	cin>>strName;
	cout<<"enter the age\n";
	cin>>nAge;
	cout<<"enter• the gender";
	cin>>strSex;
	cout<<"enter the driving license no\n";
	cin>>ndln;
	cout<<"enter the PO box\n";
	cin>>nBox;
	cout<<"enter the company\n";
	cin>>strCompany;
	cout<<"enter the destination\n";
	cin>>strDesig;
	cout<<"enter the phone no\n";
	cin>>nPhone;
	cout<<"you may proceed\n";
	cout<<"1 ..... day plan\n";
	 cout<<"2 ..... weekly plan\n";
	 cout<<"3. .... monthly plan\n";
	 cout<<"4 ..... yearly plan\n";

cin>>nPlan;
	switch(nPlan)
	{
		case 1:
			 cout<<"is it a weekend(Y or N)\n";
			 cin>>strWeekEnd;
			  if(strWeekEnd='y')
			  {
				  int temp=50;
				  cout<<"enter the no of days";
				  cin>>nDays;
				  nCost=(cars.nDays* 100)+temp;
				cout<<nCost;
			  }
			 else
			 { 
				cout<<"enter the number of days";
				cin>>nDays ; 
				nCost=cars.nDays*100;
				cout<<nCost;
			 }
			break;
		  case 2:
			  cout<<"enter the number of weeks";
			  cin>>nDays;
			  nCost=cars.nDays*90*7;
			  cout<<nCost;
			  break;
		  case 3:
			cout<<"enter the number of months";
			cin>>nDays;
			nCost=cars.nDays*65*30;
			cout<<nCost;
			break;

		 case 4:
			cout<<"enter the number of years";
			cin>>nDays;
			nCost=cars.nDays*35*365;
			cout<<nCost;
			break;

		default:
			cout<<"please check your option";
	}
}

void Car::Company()
{
	int nRate=0;
	char strdriver;
	char company[10];
		cout<<"company name";
		cin>>company;
		cout<<"do you need a driver";
		cin>>strdriver;
	if(strdriver=='y')
	{
		nRate=2000;
	}
	else
	{
		nRate=0;
	}
		char name[10];
		int dln;
		int box;
		int plan;
		int month,cost,year;
		cout<<"enter the driver's name";
		cin>>name;
		cout<<"enter the driving license number";
		cin>>dln;
		cout<<"enter the PO box";
		cin>>box;
		cout<<"please enter the plan";
		cout<<"l ..... monthly plan";
		cout<<"2 ...., yearly plan";
		cin>>plan;
	switch(plan)
	{
		case 1:
			cout<<"please enter the number of months";
			cin>>month;
			cost=(1200*month)+(nRate*month);
			cout<<cost;
		break;
		case 2:
			cout<<"please enter the number of years" ;
			cin>>year;
			cost=(9125*year)+(year*nRate*12);
			cout<<cost;
		break;

	}
	
}

void Car::Status()
{
	char choice=0;
	int counter=0;

	fstream infile;
	infile.open("car",ios::in);
	infile.seekg(0,ios::beg);
	infile.read((char*)&cars,sizeof(cars));

	while(!infile.eof( ))
	{
	if(cars.strType==choice)
	counter=counter+1 ;
	}
	if (counter<5)
	{
		cout<<"cars are available";
		cout<<"pIease continue";
	}
	else  
	{
		cout<<"no cars are available";
		cout<<"enter another type of car";
		Status ();
	}
}

void Car::ShowDetails()
{
system ("CLS");
	cout<<"customer name"<<strName;
	cout<<"age"<<nAge;
	cout<<"type"<<strType;;
	cout<<"gender"<<strSex;;
	cout<<"driving license number"<<ndln;;
	cout<<"mobi1e"<<nPhone;
	cout<<"p.o.box"<<nBox;;
	cout<<"plan"<<strPIan;
	cout<<"cost"<<nCost; 
	cout<<"press any key to continue";
	getch();
}

void Car::AddDetails()
{
fstream outfile;
char choice='y';
	while(choice=='y')
	{
	system ("CLS");
		//char ch;
		outfile.open("car",ios::app);
		cars.GetDetails();
		outfile.write((char*)&cars,sizeof(cars));
		outfile.flush();
		outfile.close();
		cout<<"any more customers";
		cin>>choice;
	}
}
void Car::ShowObject()
{  
	fstream infile; 
	infile.open("car",ios::in);
	infile.seekg(0,ios::beg);
	infile.read((char*)&cars,sizeof(cars));
	while(!infile.eof())
	{
	cars.ShowDetails();
	infile.read((char*)&cars,sizeof(cars));
	}
}

void Car::DeleteObject()
{
	int code;
	fstream infile,outfile;
	cout<<"enter the dln to be deleted";
	cin>>code;
	outfile.open("tempfile",ios::app);
	infile.open("car",ios::in);
	infile.seekg(0,ios::beg);
	infile.read((char*)&cars,sizeof(cars));
	while(infile.eof())
	{
		if(cars.ndln!=code)
		outfile.write((char*)&cars,sizeof(cars));
		infile.read((char*)&cars,sizeof(cars));
	}
	infile.close();
	outfile.close();
	remove("car");
	rename("temp","car");
}
/*void Car::Modify()
{
	fstream file;
	int code;
	int mod_choice,month;
  do 
	{ 
	//	clrscr();
		cout<<"modify menu"<<'\n';
		cout<<"change number of days\t1 "<<'\n';
		cout<<"change contact person\t2"<<'\n';
		cout<<"mobile number\t3"<<'\n';
		cout<<"exit modify menu\t4"<<'\n';
		 cout<<"PLEASE ENTER YOUR CHOICE\t\n";
		cin>>mod_choice;
if(mod_choice<4)
{
	cout<<"driving license number";
	cin>>code;
	file.open("car",ios::app);
	file.seekg(0,ios::beg);
	file.read((char*)&cars,sizeof(cars));
	int n=file.tellg();
	while(!file.eof());
	{
		if (code==cars.ndln)
		{
			switch(mod_choice)
			{
				case 1:
				system ("CLS");
					cout<<"enter the number of days";
					cin>>month;
					file.seekg(n-sizeof(cars));
					file.write((char*)&cars,sizeof(cars));
					file.flush();
				break;
				case 2:
					system ("CLS"); 
					cout<<"enter the contact person";
					  gets(cars.strName);
					  file.seekg(n-sizeof(cars));
					//file.flush((char*)&cars,sizeof(cars));
					file.flush();
				break;
				 case 3:
					system ("CLS");
					cout<<"enter the new phone number";
					cin>>cars.nPhone;;
					file.seekg(n-sizeof(cars));
					file.write((char*)&cars,sizeof(cars));
					file.flush();
				break;
				 default:
				file.read((char*)&cars,sizeof(cars));
				n=file.tellg();
			}

		file.close();
		
	}
 }while(mod_choice !=4);
system ("CLS");
	cout<<"you ended your modifying session";
	cout<<"thank you";
}*/
void Car::Modify()
{
	fstream file;
	int code;
	int mod_choice,month;
    do 
	{ 

			//	clrscr();
		cout<<"modify menu"<<'\n';
		cout<<"change number of days\t1 "<<'\n';
		cout<<"change contact person\t2"<<'\n';
		cout<<"mobile number\t3"<<'\n';
		cout<<"exit modify menu\t4"<<'\n';
		 cout<<"PLEASE ENTER YOUR CHOICE\t\n";
		cin>>mod_choice;
		if(mod_choice<4)
		{

			cout<<"driving license number";
			cin>>code;
			file.open("car",ios::app);
			file.seekg(0,ios::beg);
			file.read((char*)&cars,sizeof(cars));
			int n=file.tellg();
			while(!file.eof());
			{
				if (code==cars.ndln)
				{
						switch(mod_choice)
					{
						case 1:
						system ("CLS");
							cout<<"enter the number of days";
							cin>>month;
							file.seekg(n-sizeof(cars));
							file.write((char*)&cars,sizeof(cars));
							file.flush();
						break;
						case 2:
							system ("CLS"); 
							cout<<"enter the contact person";
							  gets(cars.strName);
							  file.seekg(n-sizeof(cars));
							//file.flush((char*)&cars,sizeof(cars));
							file.flush();
						break;
						 case 3:
							system ("CLS");
							cout<<"enter the new phone number";
							cin>>cars.nPhone;;
							file.seekg(n-sizeof(cars));
							file.write((char*)&cars,sizeof(cars));
							file.flush();
						break;
						 default:
						file.read((char*)&cars,sizeof(cars));
						n=file.tellg();
					}
				}
				
			}
				file.close();
		} // end if
	}while(mod_choice !=4); // end do
	system ("CLS");
	cout<<"you ended your modifying session";
	cout<<"thank you";
}




void main()
{ 

	int main_choice;
	do
	{
		system ("CLS");
		cout<<"main menu\n";
		cout<<"new hire 1\n";
		cout<<"modify  2\n";
		cout<<"reports 3\n";
		cout<<"delete 4 \n";
		cout<<"show data 5\n";
		cout<<"exit 6\n";
		cout<<"enter your choice\n";
		cin>>main_choice;
			switch (main_choice)
			{
				case 1:
				cars.AddDetails();
				break;
				case 2:
					cars.Modify();
				break;
				case 3:
					//	cars.reports();
				break;
				case 4:
					cars.DeleteObject( );
				break;
				case 5:
					cars.ShowObject();
				break;
				case 6:
				 system ("CLS");
					cout<<"you have ended this session\n";
					cout<<"thank you\n";
				break;
			
			}
	}while(main_choice!= 5);

}


PLEASE HELP ME OUT!!