2. Fan-Out Wire

How do you plan to solve it?

module top_module(
    input a,
    output y1,y2,y3
    // Declare Inputs and outputs here
);
    // Module functionality here
//assign y1 =a;
//assign y2=a;
//assign y3=a;
assign {y1,y2,y3} ={3{a}};
endmodule