66. Demultiplexer

How do you plan to solve it?

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

always @(*) begin
    y = 4'b0000;

    case(s)
        2'b00: y[0] = d;
        2'b01: y[1] = d;
        2'b10: y[2] = d;
        2'b11: y[3] = d;
    endcase
end

endmodule