module demux_1x16 (in,sel,out);
input in;
input [3:0] sel;
output [15:0] out;
wire [1:0] out_w;

demux_1x2 d16_0(.in(in),.sel(sel[3]),.out(out_w[1:0]));
demux_1x8 d16_1(.in(out_w[0]),.sel(sel[2:0]),.out(out[7:0]));
demux_1x8 d16_2(.in(out_w[1]),.sel(sel[2:0]),.out(out[15:8]));

endmodule