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=0;
case(s)
2'b00:y[0]=d;
2'b01:y[1]=d;
2'b10:y[2]=d;
2'b11:y[3]=d;
default y=4'b0000;
endcase 
end
endmodule