What is Hashing?

Top 20 Hashing Technique based Interview Questions

Last Updated : 24 Feb, 2025

Hashing is a powerful technique in Data Structures and Algorithms (DSA) that involves mapping data to a fixed-size value using a hash function. The key advantage of hashing is its ability to provide fast lookups, often achieving constant time complexity, O(1), for operations like searching and inserting elements. However, a good hash function is essential to minimize collisions, where multiple inputs produce the same hash value.

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What is Hashing?

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