{"abstract":"Batch padding rounds down to a length multiple.","category":"Sequence batch packing","checks":6,"contract":"Return the smallest multiple of positive multiple that is at least the maximum length; empty input returns zero.","contract_signature":"lengths, multiple","evaluation_group":"w3-seqpack-padding-multiple-v1","failed_approach":"Adding a full extra bucket fixes nonmultiples but wastes a bucket for exact multiples.","family":"w3-sequence-batch-packing-padding-to-multiple","id":"FA-98051","implementations":{"attempt":{"sha256":"d0b18764d490dc1164472b218bd05e6f7f1d5118137a7994b6e5156ee737ed7c","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(lengths, multiple):\n    return ((max(lengths)+multiple-1)//multiple+1)*multiple if lengths else 0\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('between multiples', solve([2*N+1],N+1), 2*(N+1))\ncheck('already multiple', solve([2*N],N), 2*N)\ncheck('zero length', solve([0],N), 0)\ncheck('empty', solve([],N), 0)\ncheck('mixed maximum', solve([N,2*N+1,1],N), 3*N)\ncheck('unit multiple', solve([N+1],1), N+1)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"broken":{"sha256":"3fbdbec0066f6352f7a4cca62a83aab35de47b83f50aa76781f0adac6c072148","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(lengths, multiple):\n    return (max(lengths)//multiple)*multiple if lengths else 0\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('between multiples', solve([2*N+1],N+1), 2*(N+1))\ncheck('already multiple', solve([2*N],N), 2*N)\ncheck('zero length', solve([0],N), 0)\ncheck('empty', solve([],N), 0)\ncheck('mixed maximum', solve([N,2*N+1,1],N), 3*N)\ncheck('unit multiple', solve([N+1],1), N+1)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"}},"limitations":"Inputs are short integer-token lists under the stated toy contract; results do not claim compatibility with a specific training framework. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.","method":"Deterministic executable model with adversarial boundary fixtures.","provenance":{"created_by":"Failure Map","dependencies":"Python standard library","family":"w3-sequence-batch-packing-padding-to-multiple","generated_at":"2026-09-30T16:48:08.895983+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"This deterministic toy packing rule models a common boundary in preparing bounded training sequences.","root_cause":"Floor division chooses the previous bucket when maximum length is not divisible.","sha256":"f4e40efc38fa442fa089935f16540e6df098df7460193d4b3a9bcdbcf06fbb50","title":"Batch padding rounds down to a length multiple · case 01","variant":1,"variant_policy":"The fixture code references N, supplied as 1 through 5. Fixed boundary checks may repeat. These records share one mechanism and must remain together in evaluation splits.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":29.976,"exit_code":1,"observations":[{"actual":6,"check":"between multiples","expected":4,"passed":false},{"actual":3,"check":"already multiple","expected":2,"passed":false},{"actual":1,"check":"zero length","expected":0,"passed":false},{"actual":0,"check":"empty","expected":0,"passed":true},{"actual":4,"check":"mixed maximum","expected":3,"passed":false},{"actual":3,"check":"unit multiple","expected":2,"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"between multiples\", \"actual\": 6, \"expected\": 4, \"passed\": false}, {\"check\": \"already multiple\", \"actual\": 3, \"expected\": 2, \"passed\": false}, {\"check\": \"zero length\", \"actual\": 1, \"expected\": 0, \"passed\": false}, {\"check\": \"empty\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"mixed maximum\", \"actual\": 4, \"expected\": 3, \"passed\": false}, {\"check\": \"unit multiple\", \"actual\": 3, \"expected\": 2, \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":29.522,"exit_code":1,"observations":[{"actual":2,"check":"between multiples","expected":4,"passed":false},{"actual":2,"check":"already multiple","expected":2,"passed":true},{"actual":0,"check":"zero length","expected":0,"passed":true},{"actual":0,"check":"empty","expected":0,"passed":true},{"actual":3,"check":"mixed maximum","expected":3,"passed":true},{"actual":2,"check":"unit multiple","expected":2,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"between multiples\", \"actual\": 2, \"expected\": 4, \"passed\": false}, {\"check\": \"already multiple\", \"actual\": 2, \"expected\": 2, \"passed\": true}, {\"check\": \"zero length\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"empty\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"mixed maximum\", \"actual\": 3, \"expected\": 3, \"passed\": true}, {\"check\": \"unit multiple\", \"actual\": 2, \"expected\": 2, \"passed\": true}], \"passed\": false}\n"}},"member_only":{"stages":["fixed"],"fields":["implementations.fixed","verification.fixed","harness","repair"],"note":"The verified repair, its recorded checks, the repair description, and the scoring harness are available to members."}}