Сортировка структур по убыванию

//Bred10
#include <fstream.h>
#include <stdlib.h>
#include <conio.h>
struct AEROFLOT
{
char punkt [999],lit[10];
int reis;
};
//------------------------------
void Create_Strukt ()
{ ofstream F1("Aeroflot.txt");
int d,i,n;
AEROFLOT p;
cout<<"\n Vvedit k-st zapysiv \n";
cin>>n;
for(i=0; i<n; i++)
{ cout<<"\n reis"; cin>>p.reis;
 cout<<"\n Punkt pryznachennya"; cin>>p.punkt;
 cout<<"\n typ litaka";cin>>p.lit;
 F1<<p.reis<<"\t"<<p.punkt<<"\t"<<p.lit<<"\n";}
 F1.close(); }
//--------------------------------
void search ()
{ifstream F1("Aeroflot.txt");
int f=0;
while((!F1.eof())&&(f==0))
{ char *t1=new char[20];
char *t2=new char[20];
char *t3=new char[20];
F1>>t1>>t2>>t3;
int h;
cout<<"\n Vvedit No reisy";
cin>>h;
if(atoi(t1)==h)
{cout<<"\n"<<t2<<"\t"<<t3<<"\n";
f=1;}
delete[]t1;
delete[]t2;
delete[]t3;
}}
 
void main (int *p)
{ clrscr();
int d,f=0,n;
while(f==0)
{cout<<"\n Vyberit diy: \n 1.Vvid informacii. \n 2. Poshyk. \n 3. Vporadkyvannya\n";
cin>>d;
switch(d)
{ case 1:Create_Strukt();break;
  case 2:search();       break;
  case 3:Vporyadkyvannya(*p, n); break;
  case 4:f=1;            break;
  }}
getch();
}