program binrdwt(input, output);

const
LAST=1;

type
this=array[1..1024] of char;

var
binfil :file of this;
i :integer;
x :this;

begin
rewrite(binfil);
for i := 1 to LAST do
        write(binfil, x);
reset(binfil);
for i := 1 to LAST do
        read(binfil, x);
WriteLn ('OK')
end.
