{"abstract":"Equal-price buy and sell limits fail to cross.","category":"Auction allocation rules","checks":6,"contract":"Return executable volume min(buy quantity, sell quantity) when buy limit >= sell limit, else zero. All inputs nonnegative integers.","contract_signature":"buy, sell","evaluation_group":"model-9f5503da6479dd9d","failed_approach":"Testing equality alone removes profitable strict crossings.","family":"z-auction_matching-crossing-boundary","id":"FA-12721","implementations":{"attempt":{"sha256":"a6f9e59fea0428f192ae535a7d9d234143db16523f435069c65ad041081d7867","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(buy, sell):\n    return min(buy[1],sell[1]) if buy[0]==sell[0] else 0\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('equal limit', solve([10+N,3], [10+N,4]), 3)\ncheck('strict cross', solve([12,5], [10,2]), 2)\ncheck('no cross', solve([9,3], [10,3]), 0)\ncheck('zero buy size', solve([10,0], [9,3]), 0)\ncheck('zero sell size', solve([10,4], [9,0]), 0)\ncheck('zero price', solve([0,2], [0,5]), 2)\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":"d674e4a65b856ef30640c56ce0717b5ff78014f114aea5e7e2553521712e957a","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(buy, sell):\n    return min(buy[1],sell[1]) if buy[0]>sell[0] else 0\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('equal limit', solve([10+N,3], [10+N,4]), 3)\ncheck('strict cross', solve([12,5], [10,2]), 2)\ncheck('no cross', solve([9,3], [10,3]), 0)\ncheck('zero buy size', solve([10,0], [9,3]), 0)\ncheck('zero sell size', solve([10,4], [9,0]), 0)\ncheck('zero price', solve([0,2], [0,5]), 2)\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":"Offline toy model with explicit integer inputs; no strategic behavior or real market execution. 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":"z-auction_matching-crossing-boundary","generated_at":"2026-09-29T14:38:59.435574+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Deterministic teaching model for reviewing auction allocation software; not a representation of any venue or financial advice.","root_cause":"The crossing relation is strict.","sha256":"3ed13e07d4ce5f5531a26b5dd53f8f134a3a39841f5c5185f561aa2d8f52e716","title":"Equal-price buy and sell limits fail to cross · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":39.598,"exit_code":1,"observations":[{"actual":3,"check":"equal limit","expected":3,"passed":true},{"actual":0,"check":"strict cross","expected":2,"passed":false},{"actual":0,"check":"no cross","expected":0,"passed":true},{"actual":0,"check":"zero buy size","expected":0,"passed":true},{"actual":0,"check":"zero sell size","expected":0,"passed":true},{"actual":2,"check":"zero price","expected":2,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"equal limit\", \"actual\": 3, \"expected\": 3, \"passed\": true}, {\"check\": \"strict cross\", \"actual\": 0, \"expected\": 2, \"passed\": false}, {\"check\": \"no cross\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"zero buy size\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"zero sell size\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"zero price\", \"actual\": 2, \"expected\": 2, \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":43.022,"exit_code":1,"observations":[{"actual":0,"check":"equal limit","expected":3,"passed":false},{"actual":2,"check":"strict cross","expected":2,"passed":true},{"actual":0,"check":"no cross","expected":0,"passed":true},{"actual":0,"check":"zero buy size","expected":0,"passed":true},{"actual":0,"check":"zero sell size","expected":0,"passed":true},{"actual":0,"check":"zero price","expected":2,"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"equal limit\", \"actual\": 0, \"expected\": 3, \"passed\": false}, {\"check\": \"strict cross\", \"actual\": 2, \"expected\": 2, \"passed\": true}, {\"check\": \"no cross\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"zero buy size\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"zero sell size\", \"actual\": 0, \"expected\": 0, \"passed\": true}, {\"check\": \"zero price\", \"actual\": 0, \"expected\": 2, \"passed\": false}], \"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."}}