FA-40908 / Heap invariants / Member archive

Calendar queue interval upper bounds are exclusive next-bucket starts · case 03

The bounded calendar placement certificate reports an incorrect upper bounds.

Member previewVariant 3 · 3 implementations · 7 checks per implementation

Case contract

A calendar priority queue uses integer tick origin O, positive bucket width W, and B buckets. Events [id,tick] map to virtual bucket floor((tick-O)/W), then physical index modulo B, with absolute interval boundaries retained. Report virtual and physical placements, lower and upper bounds, same-cycle eligibility relative to cursor virtual bucket, and exact-boundary events.

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	`{"boundaries": ["0", "2", "3"], "cycle_eligible": ["0", "1", "2"], "lower_bounds": [3, 3, 7, 19], "physical": [0, 0, 1, 0], "upper_bounds": [3, 3, 7, 19], "virtual": [0, 0, 1, 4]}`	`{"boundaries": ["0", "2", "3"], "cycle_eligible": ["0", "1", "2"], "lower_bounds": [3, 3, 7, 19], "physical": [0, 0, 1, 0], "upper_bounds": [7, 7, 11, 23], "virtual": [0, 0, 1, 4]}`	Failed

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

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