Data Structures Ladders¶

These ladders connect reusable structures to focused practice.

Subtopic Ladders¶

Representative Solved Note¶

Dynamic Connectivity: exact rollback-DSU route for component counts under add/remove edge events
Distinct Colors: exact first small-to-large subtree-container route for one answer per rooted subtree
CVP00001: Fenwick-backed circular simulation with reset/capture logic
Range Queries and Copies: exact first persistent segment-tree route for versioned point updates and old-version range sums
Persistent List: exact first persistent split/merge treap route for branching list versions
Nearest Smaller Values: exact first monotonic-stack route where one domination rule kills dead boundary candidates forever
Salary Queries: exact key-based treap route for duplicate-safe rank differences under online updates
Cut and Paste: exact first sequence-surgery route where split/merge by position replaces explicit index maintenance
MKTHNUM - K-th Number: exact first static order-statistics route where one range is translated through value partitions
Powerful Array: exact first Mo route where one current range and one frequency-weighted score are the whole state
Vasiliy's Multiset: exact first binary-trie route for live xor-max queries with duplicates
ORDERSET - Order Statistic Set: exact first PBDS route for online rank and k-th queries on one changing ordered set
Balanced BSTs For Contests: compare-note track for AVL and the other textbook balancing families the repo intentionally does not treat as first-line contest retrieval
B-Tree Dictionary: exact first high-fanout textbook dictionary route where split-full-child is the whole insert story
Skiplist Dictionary: exact first probabilistic ordered-dictionary route where tower search and update[] splicing are the whole state
X-Fast Dictionary: exact first bounded-universe predecessor route where binary-searching the deepest existing prefix is the real idea
Reservation System: exact first augmented-BST route where subtree max_r is enough to answer online half-open overlap queries on one live interval set
Ordinary Balanced Tree: exact first self-adjusting ordered-set route and the direct bridge into link-cut tree machinery
Mergeable Heap 1: exact first meldable-heap route where singleton heaps keep unioning and delete-min names one item's current heap
HORRIBLE: exact range add + range sum lazy-propagation baseline
Range Chmin Chmax Add Range Sum: exact canonical verifier for range chmin / chmax / add / sum
Willem, Chtholly and Seniorious: exact canonical ODT route where one std::set interval partition with split / assign / walk matches the whole statement