CPP Menu driven program for maintaining EMPLOYEE details

#include<iostream.h>
#include<conio.h>
#include<fstream.h>
#include<stdio.h>
#include<string.h>
#include<process.h>
class employee
{
      int eid;
      char ename[20];
      char empaddr[30];
      char empdesig[20];
      float sal;
   public:
      void getdata();
      void putdata();
      int return_id()
      {
  return eid;
      }
}s;
ifstream fin;
ofstream fout;
void employee::getdata()
{
   cout<<"\n  Enter Employee ID : ";cin>>eid;
   cout<<"\nEnter Employee Name : ";gets(ename);
   cout<<"\n      Enter Address : ";gets(empaddr);
   cout<<"\n  Enter Designation : ";gets(empdesig);
   cout<<"\n       Enter Salary : ";cin>>sal;
}
void employee::putdata()
{
   cout<<"\n----EMPLOYEE DETAILS----";
   cout<<"\n  Employee ID = "<<eid;
   cout<<"\nEmployee Name = "<<ename;
   cout<<"\n      Address = "<<empaddr;
   cout<<"\n  Deisgnation = "<<empdesig;
   cout<<"\n       Salary = "<<sal;
}
void create()
{
   int n;
   fout.open("record.dat",ios::out|ios::binary);
   cout<<"\nEnter Number of Employees"
       <<"to be Added : ";
   cin>>n;
   for(int i=0;i<n;i++)
   {
      cout<<"\nEnter Details of Employee "<<i+1;
      cout<<"\n-----------------------------";
      s.getdata();
      fout.write((char *)&s,sizeof(s));
      cout<<"\nDetails are Added to File Successfully";
   }
   fout.close();
}
void append()
{
   fout.open("record.dat",ios::app|ios::binary);
   cout<<"\n---Enter the Details to be Appended---";
   s.getdata();
   fout.write((char *)&s,sizeof(s));
   fout.close();
}
void display()
{
   fin.open("record.dat",ios::in|ios::binary);
   while(fin.read((char *)&s,sizeof(employee)))
      if(!fin.eof()) s.putdata();
   fin.close();
}
void modify()
{
   int flag=0;
   fstream f;
   f.open("record.dat",ios::in|ios::out|ios::binary);
   long pos;
   int g;
   employee s;
   cout<<"\nEnter the ID to modify : ";cin>>g;
   while(f)
   {
      pos=f.tellg();
      f.read((char *)&s,sizeof(s));
      if(s.return_id()==g)
      {
  s.getdata();
  flag=1;
  f.seekg(pos);
  f.write((char *)&s,sizeof(s));
      }
   }
   if(flag==0)
   {
      cout<<"\nSorry ID not found";
   }
   f.close();
}
void main()
{
   int c;
   do
   {
      clrscr();
      cout<<"\n----MENU----";
      cout<<"\n1.Create\n2.Display\n3.Append"
   <<"\n4.Modify\n5.Exit";
      cout<<"\nEnter your choice : ";cin>>c;
      switch(c)
      {
  case 1: create();
   break;
  case 2: display();
   break;
  case 3: append();
   cout<<"\nNew Details are added";
   break;
  case 4: modify();
   break;
  case 5: exit(0);
 default: cout<<"\nWrong choice!!!";
       }
       cout<<"\nPress any key to continue";
       getch();
      }while(1);
}