begin
comment get bits substring from bits string;

	bits procedure bitsSubstring(bits value bb; integer value nl, nr);
	begin
		bits s, r;
		integer i, n;
		
		if nr > 1 then bb := bb shr (nr-1);
		s := r := #1; 
		n := (nl-nr+1);
		for i := 1 until n do
		begin
			r := r or s;
			s := s shl 1;
		end;
		bb := bb and r;
		bb
	end;

	bits bt, bt2;
	integer nLeft, nRight;
	read (bt);
	read(nLeft, nRight);
	if nLeft<nRight then write("error");
	bt2 := bitsSubstring(bt, nLeft, nRight);
	write(bt2);
end.