module mux_16bit_2to1 (
  sel,out,in0,in1
);


output  [15:0] out;
reg [15:0] out;
input sel;
input [15:0] in0, in1;

always@(sel or in0 or in1)
case(sel)
    0: out=in0;
    1: out=in1;
    default: $display("%m Unknown value of select: %b", sel);
    endcase

endmodule