Hash distribution
A good hash function spreads similar keys across different buckets. This version uses a rolling multiplication-and-XOR hash instead of simply adding character codes.
What is a Hash Table?
A hash table maps a key to a bucket index using a hash function. This simulator resolves collisions with separate chaining: each bucket stores a small list of key–value entries.
Average insertO(1)
Average lookupO(1)
Worst caseO(n)
Collision methodSeparate chaining
Hash table operations
Current hash calculation
hash(key) = FNV-style rolling hash mod capacity
Example hash table loaded. Choose an operation.
Items0
Capacity8
Load factor0.00
Occupied buckets0
Operation trace
- No operation yet.
History
- No operations yet.
Hash table concepts
Separate chaining
Colliding keys remain in the same bucket as separate entries. Lookup compares keys only inside the calculated bucket.
Load factor
The load factor is items / capacity. When enabled, the table doubles near 0.75 and reinserts every entry into the new bucket array.
Updating keys
Inserting an existing key changes its value without increasing the item count. Keys are compared with strict string equality.
Complexity summary
| Operation | Average | Worst case |
|---|---|---|
| Insert / Update | O(1) | O(n) |
| Lookup | O(1) | O(n) |
| Delete | O(1) | O(n) |
| Resize / Rehash | O(n) | O(n) |
| Space | O(n + m) | O(n + m) |