44. Bus Error Checker

/*Write your code here*/
module error_checker_xz(
    input  [7:0] bus,
    output all_known,
    output has_unknown,
    output [7:0] bus_if_known
);
    assign has_unknown  = (^(bus) === 1'bx);
    assign all_known    = ~has_unknown;
    assign bus_if_known = (all_known == 1) ? bus : 8'b00000000;
endmodule