17. Binary to Gray Code Converter

How do you plan to solve it?

module bin2gray4 (
    input  [3:0] bin_in,
    output [3:0] gray_out
);

    // Expanded form
    // assign gray_out[3]   = bin_in[3];
    // assign gray_out[2:0] = bin_in[2:0] ^ bin_in[3:1];

    // Compact form
    assign gray_out = bin_in ^ (bin_in >> 1);

endmodule