66. Demultiplexer

How do you plan to solve it?

module demux1to4(
    input d,
    input [1:0] s,
    output [3:0] y
);

assign y[0] = d & ~s[1] & ~s[0];
assign y[1] = d & ~s[1] &  s[0];
assign y[2] = d &  s[1] & ~s[0];
assign y[3] = d &  s[1] &  s[0];

endmodule