Типизированные файлы 2

{Программа. Типизированный файл, содержащий произвольные числа. Найти и удалить наибольшее.}

program tip;
uses crt;

var
f: file of integer;
a1, n, i, amax, nmax, na : integer;
begin
clrscr;

writeln ('Vvod kolichestva chisel');
readln (n);
assign (f, 'file.int');
rewrite (f);
randomize;

for i := 1 to n do begin
a1:=Random (100);
write (f, a1);
end;

reset (f);
clrscr;

for i :=1 to n do begin
read (f, a1);
writeln (a1);
end;

reset (f);
amax:=-1;

while not eof(f) do begin
read (f, a1);
    if a1 > amax then begin
    amax:=a1;
    nmax:=filepos (f);
    end; end;

writeln ('max = ', amax, ' nmax = ', nmax);

if (n-nmax)>2 then begin
    seek (f, nmax-1);
    read (f, a1);
    seek (f, n);
    write (f, a1);

    i:=n+1;
    na:=nmax;

    reset (f);

    while (i>0) do begin

        i:=i-1;

        seek (f, na-1);
        read (f, a1);
        seek (f, na-2);
        write (f, a1);

        na:=na+2;

    end;
    seek (f, n-1);
    truncate (f);

end  else begin

     if nmax=n-1 then begin
     seek (f, nmax);
     truncate (f);
     end else begin
     seek (f, n-1);
     read (f, a1);
     write (f, amax);
     seek (f, amax-1);
     write (f, a1);
     seek (f, n-1);
     truncate (f);
     end;
end;

reset (f);

while not eof(f) do begin
    read (f, a1);
    writeln (a1);
end;

close (f);
readln;
clrscr;
end.