17. Binary to Gray Code Converter

module bin2gray4(

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

    assign gray_out[3] = bin_in[3];
    assign gray_out[2] = bin_in[3] ^ bin_in[2];
    assign gray_out[1] = bin_in[2] ^ bin_in[1];
    assign gray_out[0] = bin_in[1] ^ bin_in[0];

endmodule