uses crt const count subjects 100 databaseFile database txt expelFile

uses crt;
const n=3; {count subjects}
      m=100;
      databaseFile='database.txt';
      expelFile='expel.txt';
type rec = record
           surname:string[30];
           mark:record
                   higherMath:integer;
                   programming:integer;
                   physics:integer;
           end;
     end;
    mas = array[1..m] of rec;
var f1:file of rec;
    pressedKey:char;
    nameFile:string;
{----------------------------------------------------------------}
procedure fillTheList(nameFile:string);
var i,k:integer;
    r:rec;
begin
    clrscr;
    assign(f1,nameFile);
    rewrite(f1);
    write('Count records: ');
    readln(k);
    for i:=1 to k do
    begin
        write('Surname: ');
        readln(r.surname);
        r.mark.higherMath:=random(4)+2;
        r.mark.programming:=random(4)+2;
        r.mark.physics:=random(4)+2;
        write(f1,r);
    end;
    close(f1);
end;
{----------------------------------------------------------------}
procedure addRecord(nameFile:string);
var i:integer;
    r:rec;
begin
    clrscr;
    assign(f1,nameFile);
    reset(f1);

    write('Surname: ');
    readln(r.surname);
    r.mark.higherMath:=random(4)+2;
    r.mark.programming:=random(4)+2;
    r.mark.physics:=random(4)+2;
    seek(f1,filesize(f1));
    write(f1,r);
    close(f1);
end;
{----------------------------------------------------------------}
procedure editRecord(nameFile:string);
var i:integer;
    r:rec;
    surname:string;
    flag:boolean;
begin
    clrscr;
    assign(f1,nameFile);
    reset(f1);

    writeln('Which surname of student we need to edit? Surname: ');
    readln(surname);
    i:=0;
    flag:=true;
    while eof(f1) or flag do
    begin
        seek(f1,i);
        read(f1,r);
        if (r.surname = surname) then
        begin
            writeln('New surname');
            readln(r.surname);
            write('Higher math: ');
            readln(r.mark.higherMath);
            write('Programming: ');
            readln(r.mark.programming);
            write('Physics: ');
            readln(r.mark.physics);
            flag:=false;
            seek(f1,i);
            write(f1,r);
        end;
        inc(i);
    end;
    close(f1);
end;
{----------------------------------------------------------------}
procedure printList(nameFile:string);
var i:integer;
    r:rec;
begin
    clrscr;
    assign(f1,nameFile);
    reset(f1);
    i:=0;
    writeln('+------------+------------+-------------+---------+');
    writeln('| Surname    | Higher math| Programming | Physics |');
    writeln('+------------+------------+-------------+---------+');
    while not eof(f1) do
    begin
        seek(f1,i);
        read(f1,r);
        write('| ',r.surname:10,' | ');
        write(r.mark.higherMath:10,' | ');
        write(r.mark.programming:11,' | ');
        write(r.mark.physics:7,' | ');
        writeln;

        inc(i);
    end;
    close(f1);
    writeln('+-------------------------------------------------+');
end;
{----------------------------------------------------------------}
procedure whoExpel(nameFileBase:string; nameFileExpel:string);
var i:integer;
    r:rec;
    f2:file of rec;
begin
    assign(f1,nameFileBase);
    assign(f2,nameFileExpel);
    reset(f1);
    rewrite(f2);
    i:=0;
    while not eof(f1) do
    begin
        seek(f1,i);
        read(f1,r);

        if (r.mark.higherMath = 2) or
           (r.mark.programming = 2) or
           (r.mark.physics = 2) then
            write(f2,r);

        inc(i);
    end;
end;
{----------------------------------------------------------------}
procedure getCommands;
begin
    window(55,1,80,25);
    writeln('Commands: ');
    writeln('1 - exit');
    writeln('2 - edit record');
    writeln('3 - add record');
    writeln('4 - cleen screen');
    writeln('5 - fill the list');
    writeln('6 - print expel list');
    writeln('7 - print all list');
    writeln('8 - form expel list');
end;
{----------------------------------------------------------------}
begin
    randomize;
    printList('list.txt');
    clrscr;
    gotoXY(20,1);
    repeat
        getCommands;
        window(1,1,80,25);
        write('Command: ');
        clreol;
        readln(pressedKey);

        window(1,2,54,25);
        case pressedKey of
            '2': editRecord(databaseFile);
            '3': addRecord(databaseFile);
            '4': clrscr;
            '5': fillTheList(databaseFile);
            '6': printList(expelFile);
            '7': printList(databaseFile);
            '8': whoExpel(databaseFile,expelFile);
        end;
    until pressedKey = '1';
end.