Data_structures terms
The right container makes every algorithm faster
Choosing the right data structure is often the difference between an algorithm that runs in milliseconds and one that times out. This category covers arrays, linked lists, trees, graphs, heaps, hash tables, and more complex structures — with focus on when to use each, what operations are fast or slow, and how they underpin the algorithms built on top of them.
B-Trees & B+ Trees
Self-balancing tree structures used in database indexes — each node holds multiple keys, keeping the tree shallow and minimising disk I/O for range queries.
2mo ago
data_structures advanced
Disjoint Set / Union-Find
A data structure tracking which elements belong to the same group — supporting near-O(1) union and find operations. Used for network connectivity, Kruskal's MST, and cycle detection.
2mo ago
data_structures advanced
Segment Trees
A tree data structure for O(log n) range queries and point updates — supporting sum, min, max over arbitrary array ranges.
2mo ago
data_structures advanced
Skip Lists
A probabilistic data structure providing O(log n) search, insert, and delete — used internally in Redis sorted sets for ZADD/ZRANGE operations.
2mo ago
data_structures advanced
Sparse Matrix Representations
COO, CSR, and DOK formats efficiently store matrices where most values are zero — avoiding storing terabytes of zeros for recommendation systems and graphs.
2mo ago
data_structures advanced
Tries (Prefix Trees) PHP 5.0+
A tree where each path from root to node spells a prefix — enabling O(m) insert, lookup, and prefix search where m is the string length, regardless of dictionary size.
2mo ago
data_structures advanced
Bloom Filter PHP 7.0+ A probabilistic data structure that tests set membership in O(1) time and O(1) space, with a tunable false-positive rate and zero false negatives.
2mo ago
data_structures advanced
LRU Cache A fixed-size cache that evicts the Least Recently Used entry when full, implemented with a hash map and doubly linked list for O(1) get and put.
2mo ago
data_structures advanced