prog in filehandling to search,remove binary file

#include<fstream.h>
#include<conio.h>
#include<stdio.h>
#include<ctype.h>
class a
{
private:
    char name[10];
    int rno;
    int s;
public:
    void input()
    {
    cout<<"enter name";
    gets(name);
    cout<<"enter rollno";
    cin>>rno;
    }
     void display()
     {
       puts(name);
       cout<<rno;
     }
     void search()
     { cout<<"enter the roll no. to be searched:";
       cin>>s;
       if(s==rno)
       {
       cout<<"roll no found";
       }
       else
       {
       cout<<"not found";
       }
     }

};

void main()
{       clrscr();
    a obj;
    //obj.input();
    //obj.display();
    //
    obj.search();
    remove("file.txt");
    ofstream ofile;
    ofile.open("file.txt",ios::app);
    ofile.write((char*)&obj,sizeof(obj));
    ofile.close();