Hash Maps and Collision Resolution
A hash map turns a key into an array index, and everything after that is collision management. This video follows a lookup through the hash function, the bucket, and the probing sequence, comparing how separate chaining and open addressing behave at the memory level and under adversarial input.
Topics covered:
- Hashing: turning a key into an array index
- Collisions and why they are mathematically inevitable
- Separate chaining: linked lists and their cache misses
- Open addressing: probing patterns and clustering
- Load factor: the threshold that triggers a resize
- Real maps: how Go, Java, and CPython implement theirs
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