I have two copies of the book, one with only 20 chapters with a glossary of the Nadsat language at the back, and another copy with all 21 chapters but no glossary. Is there an edition of the book with everything included? If so, please let me know

I have a question: Is Clockwork Orange, the 50th anniversary edition is loyal to the original text, and does it have 21 chapters? Or is it different from the original text?