Internal working of hashmap

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HashMap is a data structure that stores key-value pairs and uses hashing to efficiently retrieve values based on keys.

HashMap internally uses an array of linked lists to store key-value pairs.
When a key-value pair is added, the key is hashed to determine the index in the array where it will be stored.
If multiple keys hash to the same index, a linked list is used to handle collisions.
To retrieve a value, the key is hashed again to find the corresponding index and then the linked list is searched for the key.
HashMap provides constant-time performance for basic operations like get and put, assuming a good hash function and minimal collisions.

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