What happens if two keys hash to the same bucket in a hash table?

When two keys hash to the same bucket in a hash table, this situation is referred to as a collision. A hash table utilizes a hash function to convert a key into an index in the underlying array. Ideally, different keys would produce unique indices; however, due to the finite size of the array and the inherent limitations of hash functions, it is possible for two distinct keys to map to the same index.

In response to a collision, there are common strategies used within hash tables to handle the situation, such as chaining or open addressing. Chaining involves storing multiple keys in the same bucket, often implemented using a linked list or another data structure that can hold multiple entries. Open addressing resolves collisions by finding another open slot in the hash table according to a defined probing sequence.

The concept of a collision is central to understanding how hash tables work, and it emphasizes the importance of designing effective hash functions to minimize the occurrence of these situations. Addressing collisions properly is crucial for maintaining the performance and efficiency of the hash table in operations like searching, inserting, and deleting keys.