module main(x1, x2, y1, y2, y3);
	input x1, x2;
	output y1, y2, y3;
	wire n1;
	and
		and1(y3, x1, x2),
		and2(y2, x1, n1),
		and3(y1, x2, n1);
	not
		not1(n1, y3);
endmodule