title: Hashtables at the exam
body: <p>I failed my algorithm exam in January. I'm going to an oral exam tomorrow. I was going through the ordinary exam and answers, when there was an answer I couldn't understand. <a href="https://i.stack.imgur.com/uFagm.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/uFagm.png" alt="Here is the question"></a></p>
  
  <p>According to the answers, the answer is A. Why? 20 mod 7 is 6, but 12 mod 7 is 5 and it is empty. Hope that you would help me out here.</p>
  
  <p>PS: Sorry if the formatting is wrong</p>