80. DFF with Async Reset and Preset

How do you plan to solve it?

module dff_async_reset_preset (
    input  CLK,
    input  RST,
    input  PRE,
    input  D,
    output reg Q
);

always @ (posedge CLK or posedge RST or posedge PRE)
begin
    if(RST==1)
    Q<=0;
    else if(PRE==1)
    Q<=1;
    else 
    Q<=D;
end

endmodule