Help!!! This code get Compile Error. Why???

{$r+,n+,q+,b-}
var n,k,s,t:longint;
begin
   read(n,k);
   s:=1; t:=0;
   for t:=1 to 31 do
   begin
      s:=s*2;
      if s>n then break;
      if s>k then
      begin
         t:=t+(n-s+k-1) div k;
         break;
      end;
   end;
   writeln(t);
end.

The online judge use dephi or something like dephi instead of pascal.
In this system.
if you use i in such condition.
You'll get a CE.

for example.

for i:=1 to 10 do
  begin
    i:=i;
  end;
it means that you can't change i in the repetition.
Good luck.
By the way.
your program get a WA after i use while...do instead of FOR

> The online judge use dephi or something like dephi instead of
pascal.
> In this system.
> if you use i in such condition.
> You'll get a CE.
>
> for example.
>
> for i:=1 to 10 do
>   begin
>     i:=i;
>   end;
> it means that you can't change i in the repetition.
> Good luck.
> By the way.
> your program get a WA after i use while...do instead of FOR