B-Trees Ladder

This lane is for the first time one search-tree lesson is really about high-fanout multiway nodes instead of one binary balancing scheme.

Who This Is For

Use this lane if:

• you already understand what one ordered dictionary does
• Balanced BSTs For Contests already feels comfortable as a compare note
• you now want the classical B-tree story itself

This lane is intentionally narrow:

• one exact starter
• one flagship note built around a canonical insert/search benchmark
• one compare route against PBDS / Order Statistics Tree
• one compare route against Treap / Implicit Treap

Warm-Up

• explain what minimum degree t means
• explain why all leaves must stay at the same depth
• explain why splitting full children before descent keeps insert clean

Target skill:

• recognize when the real lesson is "multiway search tree with node capacity," not "which binary balanced tree should I use in contest code?"

Core

• search inside one node
• child selection by separator keys
• root split
• split-full-child
• exact flagship rep: B-Tree Dictionary

Target skill:

• trust the top-down insert route and understand how B-trees trade binary rotations for high fanout and splits

Stretch

• add deletion only after the search/insert route already feels automatic
• compare against PBDS / Order Statistics Tree to keep contest ROI boundaries honest
• branch to B+ trees, disk pages, or bulk loading only after the first route is stable

Target skill:

• separate textbook breadth from the repo's first-line contest retrieval routes

Retrieval Layer

• exact quick sheet -> B-Tree hot sheet
• exact starter -> b-tree-insert-search.cpp
• compare route -> Balanced BSTs For Contests
• compare route -> PBDS / Order Statistics Tree
• compare route -> Treap / Implicit Treap
• broader chooser -> Data structures cheatsheet

Repo Anchors And Compare Points

• topic page -> B-Trees
• flagship note -> B-Tree Dictionary
• compare point -> Balanced BSTs For Contests
• compare point -> PBDS / Order Statistics Tree
• compare point -> Treap / Implicit Treap
• broader routing -> Data Structures ladder

The cleanest in-repo loop here is:

1. reopen Balanced BSTs For Contests just enough to keep the binary-tree alternatives straight
2. learn the high-fanout route in B-Trees
3. solve B-Tree Dictionary
4. compare back against PBDS / Order Statistics Tree so the "breadth lane vs contest-first route" boundary stays sharp

Exit Criteria

You are ready to move on when:

• you can describe split-full-child without hesitation
• you know why B-trees are not the repo's first retrieval route for ordinary CP ordered-set work
• you can explain how high fanout reduces height

External Practice

• Open Data Structures - 14.2 B-Trees

Tutorial Link

• B-Trees