{"abstract":"Eight-digit strings starting 2-9 are expanded as if they were UPC-E.","category":"Check-digit algorithms","checks":8,"contract":"Expand an 8-digit UPC-E (number system 0 or 1, six compressed digits m1..m6, check digit) to UPC-A. By m6: 0-2 -> m1 m2 m6 0000 m3 m4 m5; 3 -> m1 m2 m3 00000 m4 m5; 4 -> m1 m2 m3 m4 00000 m5; 5-9 -> m1..m5 0000 m6. The UPC-A check (weights 3,1 from the left over the 11 digits) must equal the given check digit; return the 12-digit UPC-A string, or None for malformed or mismatching input.","contract_signature":"s","evaluation_group":"w2-check_digit_algorithms-upce-expand","failed_approach":"Accepting only number system 0 rejects legitimate number-system-1 codes.","family":"w2-check_digit_algorithms-upce-expand-number-system-gate","id":"FA-72671","implementations":{"attempt":{"sha256":"d1ee52ae5d4b7ae64ed7c1b7cca5be6d5833ec5cb2ae299f14e0b1a7c3e3f763","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(s):\n    if len(s) != 8 or not s.isascii() or not s.isdigit() or s[0] != '0':\n        return None\n    ns, m, chk = s[0], s[1:7], s[7]\n    last = m[5]\n    if last in '012':\n        body = m[0:2] + last + '0000' + m[2:5]\n    elif last == '3':\n        body = m[0:3] + '00000' + m[3:5]\n    elif last == '4':\n        body = m[0:4] + '00000' + m[4]\n    else:\n        body = m[0:5] + '0000' + last\n    a = ns + body\n    total = sum(int(ch) * (3 if i % 2 == 0 else 1) for i, ch in enumerate(a))\n    check = (10 - total % 10) % 10\n    if str(check) != chk:\n        return None\n    return a + chk\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [[['regression [\"28109420\"]', ['28109420'], None], ['regression [\"32492194\"]', ['32492194'], None], ['partial-repair [\"13813703\"]', ['13813703'], '138000001373'], ['partial-repair [\"10054749\"]', ['10054749'], '100540000079'], ['control [\"06109613\"]', ['06109613'], '061100000963'], ['control [\"08548229\"]', ['08548229'], '085200004829'], ['control [\"03909633\"]', ['03909633'], '039000000963'], ['control [\"08190253\"]', ['08190253'], '081902000053']], [['regression [\"97987994\"]', ['97987994'], None], ['regression [\"28109420\"]', ['28109420'], None], ['partial-repair [\"14227004\"]', ['14227004'], '142000002704'], ['partial-repair [\"14586929\"]', ['14586929'], '145200008699'], ['control [\"00140485\"]', ['00140485'], '001404000085'], ['control [\"04896098\"]', ['04896098'], '048960000098'], ['control [\"08639918\"]', ['08639918'], '086100003998'], ['control [\"04793431\"]', ['04793431'], '047900000341']], [['regression [\"73497295\"]', ['73497295'], None], ['regression [\"97987994\"]', ['97987994'], None], ['partial-repair [\"12345670\"]', ['12345670'], '123456000070'], ['partial-repair [\"13813703\"]', ['13813703'], '138000001373'], ['control [\"04252614\"]', ['04252614'], '042100005264'], ['control [\"01234565\"]', ['01234565'], '012345000065'], ['control [\"01234531\"]', ['01234531'], '012300000451'], ['control [\"23456781\"]', ['23456781'], None]], [['regression [\"32492194\"]', ['32492194'], None], ['regression [\"73497295\"]', ['73497295'], None], ['partial-repair [\"15067371\"]', ['15067371'], '150673000071'], ['partial-repair [\"14227004\"]', ['14227004'], '142000002704'], ['control [\"0425261a\"]', ['0425261a'], None], ['control [\"04252615\"]', ['04252615'], None], ['control [\"00000000\"]', ['00000000'], '000000000000'], ['control [\"06109613\"]', ['06109613'], '061100000963']], [['regression [\"28109420\"]', ['28109420'], None], ['regression [\"32492194\"]', ['32492194'], None], ['partial-repair [\"16526754\"]', ['16526754'], '165267000054'], ['partial-repair [\"12345670\"]', ['12345670'], '123456000070'], ['control [\"03909633\"]', ['03909633'], '039000000963'], ['control [\"08190253\"]', ['08190253'], '081902000053'], ['control [\"03793961\"]', ['03793961'], '037939000061'], ['control [\"00140485\"]', ['00140485'], '001404000085']]]\nfor label, args, expected in fixtures[N - 1]:\n    check(label, solve(*args), expected)\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":"209d0140efc03a4cfc44aeac935276664ec2a707494a58d88e5a62736eb8ae1a","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(s):\n    if len(s) != 8 or not s.isascii() or not s.isdigit():\n        return None\n    ns, m, chk = s[0], s[1:7], s[7]\n    last = m[5]\n    if last in '012':\n        body = m[0:2] + last + '0000' + m[2:5]\n    elif last == '3':\n        body = m[0:3] + '00000' + m[3:5]\n    elif last == '4':\n        body = m[0:4] + '00000' + m[4]\n    else:\n        body = m[0:5] + '0000' + last\n    a = ns + body\n    total = sum(int(ch) * (3 if i % 2 == 0 else 1) for i, ch in enumerate(a))\n    check = (10 - total % 10) % 10\n    if str(check) != chk:\n        return None\n    return a + chk\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [[['regression [\"28109420\"]', ['28109420'], None], ['regression [\"32492194\"]', ['32492194'], None], ['partial-repair [\"13813703\"]', ['13813703'], '138000001373'], ['partial-repair [\"10054749\"]', ['10054749'], '100540000079'], ['control [\"06109613\"]', ['06109613'], '061100000963'], ['control [\"08548229\"]', ['08548229'], '085200004829'], ['control [\"03909633\"]', ['03909633'], '039000000963'], ['control [\"08190253\"]', ['08190253'], '081902000053']], [['regression [\"97987994\"]', ['97987994'], None], ['regression [\"28109420\"]', ['28109420'], None], ['partial-repair [\"14227004\"]', ['14227004'], '142000002704'], ['partial-repair [\"14586929\"]', ['14586929'], '145200008699'], ['control [\"00140485\"]', ['00140485'], '001404000085'], ['control [\"04896098\"]', ['04896098'], '048960000098'], ['control [\"08639918\"]', ['08639918'], '086100003998'], ['control [\"04793431\"]', ['04793431'], '047900000341']], [['regression [\"73497295\"]', ['73497295'], None], ['regression [\"97987994\"]', ['97987994'], None], ['partial-repair [\"12345670\"]', ['12345670'], '123456000070'], ['partial-repair [\"13813703\"]', ['13813703'], '138000001373'], ['control [\"04252614\"]', ['04252614'], '042100005264'], ['control [\"01234565\"]', ['01234565'], '012345000065'], ['control [\"01234531\"]', ['01234531'], '012300000451'], ['control [\"23456781\"]', ['23456781'], None]], [['regression [\"32492194\"]', ['32492194'], None], ['regression [\"73497295\"]', ['73497295'], None], ['partial-repair [\"15067371\"]', ['15067371'], '150673000071'], ['partial-repair [\"14227004\"]', ['14227004'], '142000002704'], ['control [\"0425261a\"]', ['0425261a'], None], ['control [\"04252615\"]', ['04252615'], None], ['control [\"00000000\"]', ['00000000'], '000000000000'], ['control [\"06109613\"]', ['06109613'], '061100000963']], [['regression [\"28109420\"]', ['28109420'], None], ['regression [\"32492194\"]', ['32492194'], None], ['partial-repair [\"16526754\"]', ['16526754'], '165267000054'], ['partial-repair [\"12345670\"]', ['12345670'], '123456000070'], ['control [\"03909633\"]', ['03909633'], '039000000963'], ['control [\"08190253\"]', ['08190253'], '081902000053'], ['control [\"03793961\"]', ['03793961'], '037939000061'], ['control [\"00140485\"]', ['00140485'], '001404000085']]]\nfor label, args, expected in fixtures[N - 1]:\n    check(label, solve(*args), expected)\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":"A deterministic, bounded teaching model of the named scheme under the stated contract; not a certified validator. 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":"w2-check_digit_algorithms-upce-expand-number-system-gate","generated_at":"2026-09-29T14:48:40.560129+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Point-of-sale systems normalise zero-suppressed UPC-E labels into UPC-A keys for price lookup.","root_cause":"The number-system restriction to 0 or 1 is missing.","sha256":"d505ef1d79d3f66d4bb192f2e45c9eb8ddaadbd34ef4c77c9e403108f822824d","title":"UPC-E admits number systems other than 0 and 1 · 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":40.101,"exit_code":1,"observations":[{"actual":null,"check":"regression [\"28109420\"]","expected":null,"passed":true},{"actual":null,"check":"regression [\"32492194\"]","expected":null,"passed":true},{"actual":null,"check":"partial-repair [\"13813703\"]","expected":"138000001373","passed":false},{"actual":null,"check":"partial-repair [\"10054749\"]","expected":"100540000079","passed":false},{"actual":"061100000963","check":"control [\"06109613\"]","expected":"061100000963","passed":true},{"actual":"085200004829","check":"control [\"08548229\"]","expected":"085200004829","passed":true},{"actual":"039000000963","check":"control [\"03909633\"]","expected":"039000000963","passed":true},{"actual":"081902000053","check":"control [\"08190253\"]","expected":"081902000053","passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"regression [\\\"28109420\\\"]\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"regression [\\\"32492194\\\"]\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"partial-repair [\\\"13813703\\\"]\", \"actual\": null, \"expected\": \"138000001373\", \"passed\": false}, {\"check\": \"partial-repair [\\\"10054749\\\"]\", \"actual\": null, \"expected\": \"100540000079\", \"passed\": false}, {\"check\": \"control [\\\"06109613\\\"]\", \"actual\": \"061100000963\", \"expected\": \"061100000963\", \"passed\": true}, {\"check\": \"control [\\\"08548229\\\"]\", \"actual\": \"085200004829\", \"expected\": \"085200004829\", \"passed\": true}, {\"check\": \"control [\\\"03909633\\\"]\", \"actual\": \"039000000963\", \"expected\": \"039000000963\", \"passed\": true}, {\"check\": \"control [\\\"08190253\\\"]\", \"actual\": \"081902000053\", \"expected\": \"081902000053\", \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":39.547,"exit_code":1,"observations":[{"actual":"281200000940","check":"regression [\"28109420\"]","expected":null,"passed":false},{"actual":"324921000094","check":"regression [\"32492194\"]","expected":null,"passed":false},{"actual":"138000001373","check":"partial-repair [\"13813703\"]","expected":"138000001373","passed":true},{"actual":"100540000079","check":"partial-repair [\"10054749\"]","expected":"100540000079","passed":true},{"actual":"061100000963","check":"control [\"06109613\"]","expected":"061100000963","passed":true},{"actual":"085200004829","check":"control [\"08548229\"]","expected":"085200004829","passed":true},{"actual":"039000000963","check":"control [\"03909633\"]","expected":"039000000963","passed":true},{"actual":"081902000053","check":"control [\"08190253\"]","expected":"081902000053","passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"regression [\\\"28109420\\\"]\", \"actual\": \"281200000940\", \"expected\": null, \"passed\": false}, {\"check\": \"regression [\\\"32492194\\\"]\", \"actual\": \"324921000094\", \"expected\": null, \"passed\": false}, {\"check\": \"partial-repair [\\\"13813703\\\"]\", \"actual\": \"138000001373\", \"expected\": \"138000001373\", \"passed\": true}, {\"check\": \"partial-repair [\\\"10054749\\\"]\", \"actual\": \"100540000079\", \"expected\": \"100540000079\", \"passed\": true}, {\"check\": \"control [\\\"06109613\\\"]\", \"actual\": \"061100000963\", \"expected\": \"061100000963\", \"passed\": true}, {\"check\": \"control [\\\"08548229\\\"]\", \"actual\": \"085200004829\", \"expected\": \"085200004829\", \"passed\": true}, {\"check\": \"control [\\\"03909633\\\"]\", \"actual\": \"039000000963\", \"expected\": \"039000000963\", \"passed\": true}, {\"check\": \"control [\\\"08190253\\\"]\", \"actual\": \"081902000053\", \"expected\": \"081902000053\", \"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."}}