`timescale 1ns/1ns module top_module( input [3:0] a, b, c, d, e, input [2:0] sel, output [3:0] out ); assign out = (sel == 3'b000)?a:( (sel == 3'b001)?b: ( (sel == 3'b010)?c: ( (sel == 3'b011)?d: ( (sel == 3'b100)?e:0 ) ) ) ); endmodule