In hashing there is a hash function that maps keys to some values. But these hashing function may lead to collision that is two or more keys are mapped to same value. Chain hashing avoids collision. The idea is to make each cell of hash table point to a linked list of records that have same hash function value.
Let’s create a hash function, such that our hash table has ‘N’ number of buckets.
To insert a node into the hash table, we need to find the hash index for the given key. And it could be calculated using the hash function.
Example: hashIndex = key % noOfBuckets
Insert: Move to the bucket corresponds to the above calculated hash index and insert the new node at the end of the list.
Delete: To delete a node from hash table, calculate the hash index for the key, move to the bucket corresponds to the calculated hash index, search the list in the current bucket to find and remove the node with the given key (if found).
Please refer Hashing | Set 2 (Separate Chaining) for details.
We use a list in C++ which is internally implemented as linked list (Faster insertion and deletion).
0 1 --> 15 --> 8 2 3 4 --> 11 5 6 --> 27
- Hashing | Set 2 (Separate Chaining)
- Hashtables Chaining with Doubly Linked Lists
- Implementing our Own Hash Table with Separate Chaining in Java
- Hashing in Java
- Applications of Hashing
- Double Hashing
- Coalesced hashing
- Hashing | Set 1 (Introduction)
- Majority Element | Set-2 (Hashing)
- Hashing | Set 3 (Open Addressing)
- Practice Problems on Hashing
- Address Calculation Sort using Hashing
- Union and Intersection of two linked lists | Set-3 (Hashing)
- Rearrange characters in a string such that no two adjacent are same using hashing
- Cuckoo Hashing - Worst case O(1) Lookup!
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