Help!!! This code get Compile Error. Tell me why, pls!

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.