Data Structures Questions Medium
Linear probing and dynamic hashing are two different techniques used in hash tables to handle collisions.
Linear probing is a collision resolution technique where, if a collision occurs, the next available slot in the hash table is searched sequentially until an empty slot is found. In linear probing, the hash table is treated as a linear array, and collisions are resolved by probing adjacent slots. This means that if two keys hash to the same index, the second key will be placed in the next available slot in the array. The main advantage of linear probing is its simplicity and ease of implementation. However, it can lead to clustering, where consecutive slots in the hash table are occupied, resulting in decreased performance.
On the other hand, dynamic hashing is a technique that dynamically adjusts the size of the hash table to accommodate more keys and reduce collisions. In dynamic hashing, the hash table starts with a small initial size and grows or shrinks as needed based on the number of keys and the load factor. When a collision occurs, instead of probing adjacent slots like in linear probing, dynamic hashing uses a different hash function to determine the new location for the key. This allows for a more even distribution of keys and reduces the chances of clustering. Dynamic hashing requires more complex implementation compared to linear probing, but it can provide better performance and scalability in scenarios where the number of keys is unpredictable or can vary significantly over time.
In summary, the main difference between linear probing and dynamic hashing in hash tables is the way they handle collisions. Linear probing probes adjacent slots to find an empty slot, while dynamic hashing uses a different hash function to determine a new location for the key. Linear probing is simpler but can lead to clustering, while dynamic hashing dynamically adjusts the size of the hash table to reduce collisions and provide better performance.