İnternal working of hash map

Question

Accepted Answer

Hash map is a data structure that stores key-value pairs and uses a hash function to map keys to their corresponding values.

Hash map consists of an array of buckets, each containing a linked list of key-value pairs.
When inserting a key-value pair, the hash function is used to determine the index of the bucket where the pair should be stored.
To retrieve a value, the hash function is used to find the corresponding bucket and then search the linked list for the key.
Hash collisions can occur when two keys map to the same bucket, which can be resolved using techniques like chaining or open addressing.
Example: Java's HashMap class uses chaining to handle collisions by storing multiple key-value pairs in the same bucket.

Popular interview questions of Software Engineer