How does collision resolution work in a hash table?

Collision resolution in a hash table is an essential mechanism for managing scenarios where two different keys hash to the same index. This situation arises due to the finite size of the hash table. The correct approach to handle these collisions involves methods like chaining and open addressing.

Chaining is a technique where each index in the hash table points to a linked list (or another type of collection) containing all entries that hash to that index. When a collision occurs, the new entry is simply added to the list of values at that index, allowing multiple entries to be stored without losing any data.

Open addressing, on the other hand, involves finding another open index within the hash table by using a specific probing sequence. When a collision occurs, the algorithm systematically checks subsequent indices based on a defined rule (like linear probing or quadratic probing) until it finds an available slot.

Both methods ensure that all entries in the hash table can be stored and retrieved efficiently, even when collisions occur, making this approach effective for maintaining data integrity and performance in hash-based data structures.