#include<iostream>
#include<conio.h>
#include<fstream>
#include<string.h>
using namespace std;

class student
{
int rno;
char name[10];
float marks[5];
char status[5];
float percent;
public:

void get();
void put();
float sum();
char* result();
void modify();
};
void student::get()
{
cout<<"ENTER ROLL NO.:";
cin>>rno;
cout<<"ENTER NAME:";
cin.ignore();
cin.getline(name,10);
cout<<"\nENTER MARKS IN 5 SUBJECTS:";
for(int i=0;i<5;i++)
cin>>marks[i];
result();

}
void student::put()
{
cout<<"\n\nROLL NO.:"<<rno;
cout<<"\nNAME:"<<name;
cout<<"\nMARKS IN 5 SUBJECTS:";
for(int i=0;i<5;i++)
cout<<marks[i]<<",";
cout<<"\nPERCENTAGE:"<<percent<<"%";
cout<<"\nSTATUS:"<<status;
}
float student::sum()
{
float total=0;
for(int i=0;i<5;i++)
total+=marks[i];
return total;
}
char* student::result()
{

percent=sum()/5;
if(percent>=33)
strcpy(status,"PASS");
else
strcpy(status,"FAIL");
return status;
}
void student::modify()
{
percent+=10;
}
void write()
{
ofstream fout;
fout.open("student.dat",ios::out|ios::app|ios::binary);
student s;
char ans;
do
{
s.get();
fout.write((char*)&s,sizeof(s));
cout<<"\nDO U WANT TO ADD MORE:";
cin>>ans;
}while(ans=='y'||ans=='Y');
fout.close();
}
void read()
{
ifstream fin;
fin.open("student.dat",ios::binary);
student s;
while(fin.read((char*)&s,sizeof(s)))
{
s.put();
}
fin.close();
}
void pass()
{
ifstream fin;
fin.open("student.dat",ios::in|ios::binary);
student s;
while(fin.read((char*)&s,sizeof(s)))
{
if(!strcmp(s.result(),"PASS"))
s.put();
}
fin.close();
}
void grace()
{
fstream f;
f.open("student.dat",ios::in|ios::binary|ios::out);
student s;

while(f.read((char*)&s,sizeof(s)))
{
if(!strcmp(s.result(),"FAIL")==0)
{
s.modify();

f.seekp(-1*sizeof(s),ios::cur);
f.write((char*)&s,sizeof(s));
f.seekp(-1*sizeof(s),ios::cur);
f.read((char*)&s,sizeof(s));
s.put();

}
}
}
void copy()
{
ifstream fin;
ofstream fout;
student s;
fin.open("student.dat",ios::binary);
fout.open("fail.dat",ios::binary);
while(fin.read((char*)&s,sizeof(s)))
{
if(!strcmpi(s.result(),"FAIL"))
fout.write((char*)&s,sizeof(s));
}

}

int main()
{
int ch;
char ans;
do
{
system("cls");
cout<<endl<<endl;
cout<<"*****************************************************************************";
cout<<endl<<endl;
cout<<"MENU:\n";
cout<<"1.ADD RECORDS\n";
cout<<"2.DISPLAY RECORDS\n";
cout<<"3.RECORD OF PASSED STUDENTS\n";
cout<<"4.GRACE\n";
cout<<"5.COPY DETAILS OF FAILED STUDENTS TO OTHER FILE\n";

cout<<"ENTER YOUR CHOICE:";
cin>>ch;
switch(ch)
{
case 1:write();break;
case 2:read();break;
case 3:pass();break;
case 4:grace();break;
case 5:copy();break;

default:cout<<"INVALID CHOICE";
}
cout<<"\nDO YOU WANT TO REVISIT HOMEPAGE(y/n):";
cin>>ans;
}while(ans!='n');
cout<<"\n*****************************************************************************";
getch();
return 0;
}