Hashmap and working of hashmap

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Accepted Answer

Hashmap is a data structure that stores key-value pairs and allows for fast retrieval of values based on keys.

Hashmap is implemented using an array of linked lists, where each element in the array is a bucket that can store multiple key-value pairs.
To store a key-value pair in a hashmap, the key is hashed to determine the index in the array where the pair will be stored.
Hash collisions can occur when multiple keys hash to the same index, and in such cases, the hashmap uses a collision resolution strategy like chaining or open addressing.
Retrieving a value from a hashmap involves hashing the key to find the corresponding bucket and then searching the linked list in that bucket for the key.
Hashmaps offer constant-time average-case complexity for insertion, deletion, and lookup operations, making them efficient for storing and retrieving data.

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