FA-40965 / Heap invariants / Member archive

Heap frontier expands both actual zero-based children and no parent alias · case 05

The bounded heap frontier certificate reports an incorrect children.

Member previewVariant 5 · 3 implementations · 7 checks per implementation

Case contract

A read-only best-first traversal of a valid binary min heap has already emitted parent slot p and a frontier of distinct slots. Insert p children that exist into the frontier, order by (key,index), and choose next. Return new frontier, chosen slot, child additions, traversal output key, preserved heap, and next frontier after selection. Initial frontier excludes p and its children.

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 2	`{"children": [0, 1], "chosen": 2, "frontier_after": [1], "heap_after": [1, 7, 2], "next_key": 2, "ready": [2, 1]}`	`{"children": [1, 2], "chosen": 2, "frontier_after": [1], "heap_after": [1, 7, 2], "next_key": 2, "ready": [2, 1]}`	Failed

MEMBER ARCHIVE

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

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