Search operation in quadratic probing

The search operation is one of the primary operations on a hash table and is used to retrieve the value of a key as stored in the hash table. The implementation is encapsulated in the search function and relies on the quadratic probing collision resolution scheme to look for a value in the internal array. Let us look at the algorithm and implementation of the search operation in a hash table using quadratic probing.

Algorithm

The search operation is quite simple: We only need to calculate the index (hash code) for the given key and then search for the key at the index. However, the hash table could have a collision for the given key, so we follow the quadratic probing scheme to search for it.

Once we calculate the index (hash code) for the given key, we search the array starting from that index using the quadratic function until we find an occupied record with the given key, hit an empty record, or finish the probe sequence. Let us look at the different cases separately to understand how the search operation is implemented in a hash table that uses a quadratic probing scheme for collision resolution.

1. The key is present in the table