A warehouse console adjusts capacity estimates across intervals, answers reporting-chain questions, totals quantities in rectangular storage zones, and keeps an asset-ID set. Each index has a separate invariant. The segment tree postpones work only on fully covered intervals; the reporting table is valid only for one fixed rooted tree; the two-dimensional Fenwick grid converts assignments into differences; and a Robin Hood table preserves probe order when deleting a key. Compare outputs against an array, a plain parent map, a matrix scan, and a Python set.
Project: audit capacity ranges and warehouse indexes
Acceptance trace
Start capacity values 61, 47, 83, 26, 52, 19. Subtract 7 over [1, 5), add 20 over [3, 6), and require a minimum of 39 in [2, 6). Build a reporting tree where E-19 manages E-26 and E-47, E-26 manages E-52 and E-61, and E-47 manages E-83; the common manager for E-52 and E-83 is E-19. Put 47 units at grid cell (1, 2), 61 at (2, 3), and 19 at (3, 4). Rectangle [1, 3) by [2, 4) sums to 108 before replacing the first quantity with 26, then 87. Insert five colliding asset IDs into seven slots, delete 26, and confirm 33 remains findable.
Expected output
range-minimum=39 common-manager=E-19
rectangle-before=108 rectangle-after=87
asset-33-present=true live=19,33,47,54Cost and boundary review
Lazy range updates and minimum queries take O(log N) time over a fixed array. Binary lifting spends O(N log N) preprocessing and answers common-ancestor requests in O(log N). A dense two-dimensional Fenwick grid spends O(RC) memory and O(log R log C) time per assignment or rectangle. The fixed-capacity hash set has O(C) worst-case probes and can reject insertion when full. Test invalid bounds and malformed trees explicitly. These examples are local single-process models; none supplies transactional atomicity, live topology edits, or synchronized readers.
Common Mistakes
- Do not lose a deferred update during partial descent.
- Do not use a stale ancestor table after moving an employee.
- Do not omit an inclusion-exclusion corner.
- Do not leave a hash deletion hole before displaced keys.
