Question

3. (20 points) In open addressing with double hashing, we have h(k,i) hi(k)+ih2(k) mod m, where hi(k) and h2(k) is an auxiliary functions. In class we saw that h2(k) and m should not have any common divisors (other than 1). Explain what can go wrong if h2(k) and m have a common divisor. In particular, consider following scenario: m- 16, h(k) k mod (m/8) and h2(k)-m/2 and the keys are ranged from 0 to 15. Using this hash function, can the hash table be completely filled? How many distinct keys can be inserted into the hash tables Explain your answer in details. (Note that we don't use linked-list in open addressing).

Answer 1

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