Hashing Questions
The main difference between double hashing and chaining is the way collisions are handled in each method.
In double hashing, when a collision occurs (i.e., when two or more keys hash to the same index), a secondary hash function is used to calculate an alternative index for the key. This alternative index is then probed until an empty slot is found, allowing the key to be inserted. This process helps to distribute the keys more evenly and reduces the likelihood of collisions.
On the other hand, chaining involves creating a linked list at each index of the hash table. When a collision occurs, the key is simply added to the linked list at the corresponding index. This means that multiple keys can be stored at the same index, forming a chain of elements. To retrieve a specific key, the hash function is used to find the correct index, and then the linked list is traversed to find the desired key.
In summary, double hashing uses a secondary hash function to find an alternative index for collision resolution, while chaining uses linked lists to store multiple keys at the same index.