FA-40513 / Heap invariants / Member archive

Loser tree counts a key comparison only when both runs are active · case 03

The bounded loser match certificate reports an incorrect comparisons.

Member previewVariant 3 · 3 implementations · 7 checks per implementation

Case contract

A loser-tree match compares challenger [run,key,active] and defender likewise. Exhausted entries lose to active entries, ties prefer lower run id, both exhausted produce no winner. Return winner run, stored loser run, active match cost, exhausted runs, winning key, and replay continuation run.

Why this case matters

This isolates an internal heap representation or priority-structure invariant using deterministic finite records.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
regression certificate 1	`{"comparisons": 1, "continuation": 2, "exhausted": [1], "key": 5, "stored_loser": 1, "winner": 2}`	`{"comparisons": 0, "continuation": 2, "exhausted": [1], "key": 5, "stored_loser": 1, "winner": 2}`	Failed

MEMBER ARCHIVE

The complete case is available to members.

This record includes three runnable implementations, regression fixtures, execution results, and source hashes.

Member access is invitation-based. Sign in with your invited account to inspect the sources.