What is the application of linked list arrays in the implementation of the HashMap data structure?

In the implementation of the HashMap data structure, an array of linked lists is used to handle collisions when hashing keys.

Main idea:

• HashMap stores elements in an array (buckets), indexed by the hash of the key.
• If multiple keys have the same hash (collision), their elements are placed in a linked list associated with the corresponding bucket.

This allows efficient storage and retrieval of elements even in the presence of collisions, by traversing the linked lists within the buckets.

Example:

• Keys "apple" and "elppa" may have the same hash and fall into the same bucket.
• A linked list is created in this bucket, storing pairs (key, value) for both keys.

This approach is simple to implement and provides acceptable performance with a moderate number of collisions.