Góp ý code ghi file bài này giùm mình nhé! cảm ơn mọi người

#pragma once
#include<fstream>
#include<iomanip>
#include<ctype.h>
#include<conio.h>

#include<iostream>
#include<stdlib.h>
using namespace std;
class hs
{

private:
 char ten[100];
 int namsinh;
 float toan,ly,hoa,van,su,dia,anh,tin,td;
public:
 void nhap();
 void xuatten();
 void xuatnamsinh();
 void monthilai();
 void ghifile();
 float dtb();
 int hanhdong();
 hs(void);
 ~hs(void);
};
void hs::nhap()
{
 cout<<"
Ten: ";
 fflush(stdin);
 gets(ten);
 do{
  cout<<"
nam sinh: ";
  cin>>namsinh;
  if(namsinh<1900 || namsinh >2100) cout<<"
khong hop le! nhap lai!!";
 }while(namsinh<1900 || namsinh >2100);
 cout<<"
nhap diem cac mon:";
 do{
  cout<<"
Toan: ";cin>>toan;
  if(toan<0 || toan>10) cout<<"
khong hop le! nhap lai!!";
 }while(toan<0 || toan>10);
 do{
  cout<<"
Ly: ";cin>>ly;
  if(ly<0 || ly>10) cout<<"
khong hop le! nhap lai!!";
 }while(ly<0 || ly>10);
 do{
  cout<<"
hoa: ";cin>>hoa;
  if(hoa<0 || hoa>10) cout<<"
khong hop le! nhap lai!!";
 }while(hoa<0 || hoa>10);
 do{
  cout<<"
van: ";cin>>van;
  if(van<0 || van>10) cout<<"
khong hop le! nhap lai!!";
 }while(van<0 || van>10);
 do{
  cout<<"
su: ";cin>>su;
  if(su<0 || su>10) cout<<"
khong hop le! nhap lai!!";
 }while(su<0 || su>10);
 do{
  cout<<"
dia: ";cin>>dia;
  if(dia<0 || dia>10) cout<<"
khong hop le! nhap lai!!";
 }while(dia<0 || dia>10);
 do{
  cout<<"
anh: ";cin>>anh;
  if(anh<0 || anh>10) cout<<"
khong hop le! nhap lai!!";
 }while(anh<0 || anh>10);
 do{
  cout<<"
tin: ";cin>>tin;
  if(tin<0 || tin>10) cout<<"
khong hop le! nhap lai!!";
 }while(tin<0 || tin>10);
  ghifile();
}
int hs::hanhdong()
{
 if(toan<5 || ly<5 || hoa<5 || van<5 || su<5||dia<5||anh<5||tin<5) return -1;
 if(dtb()>7) return 1;
 return 0;
}
void hs::xuatten()
{
 cout<<ten;
}
void hs::monthilai()
{
 cout<<"
*nhung mon thi lai:";
 if(toan<5) cout<<"
	toan";
 if(ly<5) cout<<"
	ly";
 if(hoa<5) cout<<"
	hoa";
 if(van<5) cout<<"
	van";
 if(su<5) cout<<"
	su";
 if(dia<5) cout<<"
	dia";
 if(anh<5) cout<<"
	anh";
 if(tin<5) cout<<"
	tin";
}
void hs::xuatnamsinh()
{
 cout<<namsinh;
}
float hs::dtb()
{
 return (toan+ly+hoa+van+su+dia+anh+tin)/8;
}
void hs::ghi_file()
{
    fstream f;
    f.open("SINHVIEN.TXT", ios::binary|ios::app|ios::out);
    f.write((char*)this, sizeof(*this));
    f.close();
}
hs::hs(void)
{
}


hs::~hs(void)
{
}

…

#pragma once
class danhsachhs
{
private:
 hs x[1000];
 int n;
 float td;
public:
 void nhap();
 void xuatthilai();
 void xuatthitotnghiep();
 void xuatluanvan();
 danhsachhs(void);
 ~danhsachhs(void);
};

void danhsachhs::nhap()
{
 int k,i=1;
 cout<<"
*nhap hoc sinh 1";
 x[0].nhap();
 do{
  cout<<"
------menu-----";
  cout<<"
| 1.nhap tiep.|";
  cout<<"
| 0.ket thuc. |";
  cout<<"
---------------";
  do{
   cout<<"
lua chon cua ban: ";
   cin>>k;
  }while(k!=1 && k!=0);
  if(k==1)
  {
   cout<<"
	* nhap hoc sinh "<<i+1;
   x[i++].nhap();
  }
 }while(k==1)
 n=i;
}
void danhsachhs::xuatthilai()
{
 cout<<"
	* DANH SACH THI LAI *
";
 int i,j=0;
 for(i=0;i<n;i++)
  if(x[i].hanhdong()==-1)
  {
   j++;
   cout<<"
"<<j<<". ";x[i].xuatten();cout<<" - ";x[i].xuatnamsinh();cout<<"
";
   x[i].monthilai();
  }
 if(j==0) cout<<"
	khong co!";
}
void danhsachhs::xuatthitotnghiep()
{
 cout<<"
	* DANH SACH THI TOT NGHIEP *
";
 int i,j=0;
 for(i=0;i<n;i++)
  if(x[i].hanhdong()==0)
  {
   j++;
   cout<<"
"<<j<<". ";x[i].xuatten();cout<<" - ";x[i].xuatnamsinh();cout<<"
";
  }
 if(j==0) cout<<"
	khong co!
";
}
void danhsachhs::xuatluanvan()
{
 cout<<"
	* DANH SACH LAM LUAN VAN TOT NGHIEP *
";
 int i,j=0;
 for(i=0;i<n;i++)
  if(x[i].hanhdong()==1)
  {
   j++;
   cout<<"
"<<j<<". ";x[i].xuatten();cout<<" - ";x[i].xuatnamsinh();cout<<"
";
  }
 if(j==0) cout<<"
	khong co!
";
}
danhsachhs::danhsachhs(void)
{
}


danhsachhs::~danhsachhs(void)
{
}




void main()
{
 danhsachhs x;
 
 x.nhap();
 cout<<"
-------------------------------------------------------
";
 x.xuatluanvan();
 cout<<"
-------------------------------------------------------
";
 x.xuatthitotnghiep();
 cout<<"
-------------------------------------------------------
";
 x.xuatthilai();
 hs a;
 cout<<"
 ghi file";
 a.ghifile();
  system("pause");
}