Question

What is the best definition of a collision in a hash table?

(a) Two entries are identical except for their keys.
(b) Two entries with different data have the exact same key.
(c) Two entries with different keys have the same exact hash value.
(d) Two entries with the exact same key have different hash values.
(e) None of the other options are correct.

Answer 1

A collision in a hash table occurs when two entries have the same exact hash value, but different keys. This can be resolved using separate chaining or open addressing.

Step-by-step explanation:

A collision in a hash table occurs when two entries have the same exact hash value, but different keys. This is option (c) - Two entries with different keys have the same exact hash value. When this happens, a collision resolution mechanism is needed to handle the collision.

One common way to handle collisions is through separate chaining or open addressing. With separate chaining, each slot in the hash table contains a linked list of entries that have the same hash value. With open addressing, if a collision occurs, the table is probed to find an open slot to store the entry.

By understanding collisions and the different collision resolution mechanisms, we can effectively implement and use hash tables to store and retrieve data efficiently.