Softtwig Technology Solutions Full Stack Developer Interview Questions and Answers

HashMap internally uses an array of linked lists to store key-value pairs.

• HashMap uses hashing to determine the index of the key in the array.

• If multiple keys hash to the same index, a linked list is used to handle collisions.

• When retrieving a value, the key is hashed to find the index and then the linked list is traversed to find the key-value pair.

Hashset stores unique elements only, while hashmap stores key-value pairs.

• Hashset does not allow duplicate elements, while hashmap allows duplicate values but not duplicate keys.

• Hashset uses a single value to store elements, while hashmap uses key-value pairs.

• Example: Hashset can be used to store a list of unique usernames, while hashmap can be used to store user information with a unique user ID as the key.