{"abstract":"House 123 gets delivery point 12 instead of 23.","category":"Postal address normalization","checks":7,"contract":"Input [zip5, plus4, primary]. The delivery point is the last two of the leading digits of the primary number, zero-padded to two, or \"99\" when there are none. With a plus-four the digit string is zip5 + plus4 + delivery point, otherwise zip5 alone. Append the check digit (10 - digit sum mod 10) mod 10.","evaluation_group":"w2-postal-address-normalization-delivery-point","failed_approach":"Slicing positions 1 to 3 works for three-digit numbers only.","family":"w2-postal-address-normalization-delivery-point-dp-slice","id":"FA-96146","implementations":{"attempt":{"sha256":"be5532b7da3939e174ee139607c76ad7b61558b41e44fee01bf169e669b55d9a","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(x):\n    zip5, plus4, primary = x\n    lead = ''\n    for c in primary:\n        if not c.isdigit():\n            break\n        lead += c\n    dp = lead[1:3].zfill(2) if lead else '99'\n    digits = zip5 + plus4 + dp if plus4 else zip5\n    check = (10 - sum(int(c) for c in digits) % 10) % 10\n    return digits + str(check)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [[['three-digit house number', ['12341', '6789', '123'], '123416789234'], ['four-digit house number', ['12341', '6789', '4567'], '123416789676'], ['one-digit house number is padded', ['12341', '6789', '7'], '123416789072'], ['no house digits uses the default', ['12341', '6789', 'RR'], '123416789991'], ['hyphenated house number stops at the hyphen', ['12341', '6789', '12-4'], '123416789126'], ['five-digit code has no delivery point', ['12341', '', '123'], '123419'], ['digit sum already a multiple of ten', ['19000', '0000', '300'], '190000000000']], [['three-digit house number', ['23442', '6789', '123'], '234426789230'], ['four-digit house number', ['23442', '6789', '4567'], '234426789672'], ['one-digit house number is padded', ['23442', '6789', '7'], '234426789078'], ['no house digits uses the default', ['23442', '6789', 'RR'], '234426789997'], ['hyphenated house number stops at the hyphen', ['23442', '6789', '12-4'], '234426789122'], ['five-digit code has no delivery point', ['23442', '', '123'], '234425'], ['digit sum already a multiple of ten', ['28000', '0000', '300'], '280000000000']], [['three-digit house number', ['34543', '6789', '123'], '345436789236'], ['four-digit house number', ['34543', '6789', '4567'], '345436789678'], ['one-digit house number is padded', ['34543', '6789', '7'], '345436789074'], ['no house digits uses the default', ['34543', '6789', 'RR'], '345436789993'], ['hyphenated house number stops at the hyphen', ['34543', '6789', '12-4'], '345436789128'], ['five-digit code has no delivery point', ['34543', '', '123'], '345431'], ['digit sum already a multiple of ten', ['37000', '0000', '300'], '370000000000']], [['three-digit house number', ['45644', '6789', '123'], '456446789232'], ['four-digit house number', ['45644', '6789', '4567'], '456446789674'], ['one-digit house number is padded', ['45644', '6789', '7'], '456446789070'], ['no house digits uses the default', ['45644', '6789', 'RR'], '456446789999'], ['hyphenated house number stops at the hyphen', ['45644', '6789', '12-4'], '456446789124'], ['five-digit code has no delivery point', ['45644', '', '123'], '456447'], ['digit sum already a multiple of ten', ['46000', '0000', '300'], '460000000000']], [['three-digit house number', ['56745', '6789', '123'], '567456789238'], ['four-digit house number', ['56745', '6789', '4567'], '567456789670'], ['one-digit house number is padded', ['56745', '6789', '7'], '567456789076'], ['no house digits uses the default', ['56745', '6789', 'RR'], '567456789995'], ['hyphenated house number stops at the hyphen', ['56745', '6789', '12-4'], '567456789120'], ['five-digit code has no delivery point', ['56745', '', '123'], '567453'], ['digit sum already a multiple of ten', ['55000', '0000', '300'], '550000000000']]]\nfor label, arg, expected in fixtures[N - 1]:\n    check(label, solve(arg), 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":"95282c860dfb877793cbe502e5197a25e81541b441254ca6d8a8e58717f5d270","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(x):\n    zip5, plus4, primary = x\n    lead = ''\n    for c in primary:\n        if not c.isdigit():\n            break\n        lead += c\n    dp = lead[:2].zfill(2) if lead else '99'\n    digits = zip5 + plus4 + dp if plus4 else zip5\n    check = (10 - sum(int(c) for c in digits) % 10) % 10\n    return digits + str(check)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [[['three-digit house number', ['12341', '6789', '123'], '123416789234'], ['four-digit house number', ['12341', '6789', '4567'], '123416789676'], ['one-digit house number is padded', ['12341', '6789', '7'], '123416789072'], ['no house digits uses the default', ['12341', '6789', 'RR'], '123416789991'], ['hyphenated house number stops at the hyphen', ['12341', '6789', '12-4'], '123416789126'], ['five-digit code has no delivery point', ['12341', '', '123'], '123419'], ['digit sum already a multiple of ten', ['19000', '0000', '300'], '190000000000']], [['three-digit house number', ['23442', '6789', '123'], '234426789230'], ['four-digit house number', ['23442', '6789', '4567'], '234426789672'], ['one-digit house number is padded', ['23442', '6789', '7'], '234426789078'], ['no house digits uses the default', ['23442', '6789', 'RR'], '234426789997'], ['hyphenated house number stops at the hyphen', ['23442', '6789', '12-4'], '234426789122'], ['five-digit code has no delivery point', ['23442', '', '123'], '234425'], ['digit sum already a multiple of ten', ['28000', '0000', '300'], '280000000000']], [['three-digit house number', ['34543', '6789', '123'], '345436789236'], ['four-digit house number', ['34543', '6789', '4567'], '345436789678'], ['one-digit house number is padded', ['34543', '6789', '7'], '345436789074'], ['no house digits uses the default', ['34543', '6789', 'RR'], '345436789993'], ['hyphenated house number stops at the hyphen', ['34543', '6789', '12-4'], '345436789128'], ['five-digit code has no delivery point', ['34543', '', '123'], '345431'], ['digit sum already a multiple of ten', ['37000', '0000', '300'], '370000000000']], [['three-digit house number', ['45644', '6789', '123'], '456446789232'], ['four-digit house number', ['45644', '6789', '4567'], '456446789674'], ['one-digit house number is padded', ['45644', '6789', '7'], '456446789070'], ['no house digits uses the default', ['45644', '6789', 'RR'], '456446789999'], ['hyphenated house number stops at the hyphen', ['45644', '6789', '12-4'], '456446789124'], ['five-digit code has no delivery point', ['45644', '', '123'], '456447'], ['digit sum already a multiple of ten', ['46000', '0000', '300'], '460000000000']], [['three-digit house number', ['56745', '6789', '123'], '567456789238'], ['four-digit house number', ['56745', '6789', '4567'], '567456789670'], ['one-digit house number is padded', ['56745', '6789', '7'], '567456789076'], ['no house digits uses the default', ['56745', '6789', 'RR'], '567456789995'], ['hyphenated house number stops at the hyphen', ['56745', '6789', '12-4'], '567456789120'], ['five-digit code has no delivery point', ['56745', '', '123'], '567453'], ['digit sum already a multiple of ten', ['55000', '0000', '300'], '550000000000']]]\nfor label, arg, expected in fixtures[N - 1]:\n    check(label, solve(arg), 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"},"fixed":{"sha256":"a1af4429ffda66938003d4e30131d093702831f4e549075692d328dc8d7ab5f6","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(x):\n    zip5, plus4, primary = x\n    lead = ''\n    for c in primary:\n        if not c.isdigit():\n            break\n        lead += c\n    dp = lead[-2:].zfill(2) if lead else '99'\n    digits = zip5 + plus4 + dp if plus4 else zip5\n    check = (10 - sum(int(c) for c in digits) % 10) % 10\n    return digits + str(check)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [[['three-digit house number', ['12341', '6789', '123'], '123416789234'], ['four-digit house number', ['12341', '6789', '4567'], '123416789676'], ['one-digit house number is padded', ['12341', '6789', '7'], '123416789072'], ['no house digits uses the default', ['12341', '6789', 'RR'], '123416789991'], ['hyphenated house number stops at the hyphen', ['12341', '6789', '12-4'], '123416789126'], ['five-digit code has no delivery point', ['12341', '', '123'], '123419'], ['digit sum already a multiple of ten', ['19000', '0000', '300'], '190000000000']], [['three-digit house number', ['23442', '6789', '123'], '234426789230'], ['four-digit house number', ['23442', '6789', '4567'], '234426789672'], ['one-digit house number is padded', ['23442', '6789', '7'], '234426789078'], ['no house digits uses the default', ['23442', '6789', 'RR'], '234426789997'], ['hyphenated house number stops at the hyphen', ['23442', '6789', '12-4'], '234426789122'], ['five-digit code has no delivery point', ['23442', '', '123'], '234425'], ['digit sum already a multiple of ten', ['28000', '0000', '300'], '280000000000']], [['three-digit house number', ['34543', '6789', '123'], '345436789236'], ['four-digit house number', ['34543', '6789', '4567'], '345436789678'], ['one-digit house number is padded', ['34543', '6789', '7'], '345436789074'], ['no house digits uses the default', ['34543', '6789', 'RR'], '345436789993'], ['hyphenated house number stops at the hyphen', ['34543', '6789', '12-4'], '345436789128'], ['five-digit code has no delivery point', ['34543', '', '123'], '345431'], ['digit sum already a multiple of ten', ['37000', '0000', '300'], '370000000000']], [['three-digit house number', ['45644', '6789', '123'], '456446789232'], ['four-digit house number', ['45644', '6789', '4567'], '456446789674'], ['one-digit house number is padded', ['45644', '6789', '7'], '456446789070'], ['no house digits uses the default', ['45644', '6789', 'RR'], '456446789999'], ['hyphenated house number stops at the hyphen', ['45644', '6789', '12-4'], '456446789124'], ['five-digit code has no delivery point', ['45644', '', '123'], '456447'], ['digit sum already a multiple of ten', ['46000', '0000', '300'], '460000000000']], [['three-digit house number', ['56745', '6789', '123'], '567456789238'], ['four-digit house number', ['56745', '6789', '4567'], '567456789670'], ['one-digit house number is padded', ['56745', '6789', '7'], '567456789076'], ['no house digits uses the default', ['56745', '6789', 'RR'], '567456789995'], ['hyphenated house number stops at the hyphen', ['56745', '6789', '12-4'], '567456789120'], ['five-digit code has no delivery point', ['56745', '', '123'], '567453'], ['digit sum already a multiple of ten', ['55000', '0000', '300'], '550000000000']]]\nfor label, arg, expected in fixtures[N - 1]:\n    check(label, solve(arg), 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 toy contract over synthetic, obviously fictitious addresses. The rules are stipulated for this model only and make no claim of conformance with any postal authority standard. 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-postal-address-normalization-delivery-point-dp-slice","generated_at":"2026-09-29T14:52:20.104447+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"A wrong delivery point or check digit sends machine-sorted mail to the wrong door or rejects it.","repair":"Use the last two leading digits.","root_cause":"The slice takes the leading two digits instead of the last two.","sha256":"d9246e5ce3e1d0b7a72c5a1635a3e0522a520fa85d93d85e658539beb1f7732f","title":"Delivery point check digit: the first two house digits are used · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":37.384,"exit_code":1,"observations":[{"actual":"123416789234","check":"three-digit house number","expected":"123416789234","passed":true},{"actual":"123416789568","check":"four-digit house number","expected":"123416789676","passed":false},{"actual":"123416789009","check":"one-digit house number is padded","expected":"123416789072","passed":false},{"actual":"123416789991","check":"no house digits uses the default","expected":"123416789991","passed":true},{"actual":"123416789027","check":"hyphenated house number stops at the hyphen","expected":"123416789126","passed":false},{"actual":"123419","check":"five-digit code has no delivery point","expected":"123419","passed":true},{"actual":"190000000000","check":"digit sum already a multiple of ten","expected":"190000000000","passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"three-digit house number\", \"actual\": \"123416789234\", \"expected\": \"123416789234\", \"passed\": true}, {\"check\": \"four-digit house number\", \"actual\": \"123416789568\", \"expected\": \"123416789676\", \"passed\": false}, {\"check\": \"one-digit house number is padded\", \"actual\": \"123416789009\", \"expected\": \"123416789072\", \"passed\": false}, {\"check\": \"no house digits uses the default\", \"actual\": \"123416789991\", \"expected\": \"123416789991\", \"passed\": true}, {\"check\": \"hyphenated house number stops at the hyphen\", \"actual\": \"123416789027\", \"expected\": \"123416789126\", \"passed\": false}, {\"check\": \"five-digit code has no delivery point\", \"actual\": \"123419\", \"expected\": \"123419\", \"passed\": true}, {\"check\": \"digit sum already a multiple of ten\", \"actual\": \"190000000000\", \"expected\": \"190000000000\", \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":38.8,"exit_code":1,"observations":[{"actual":"123416789126","check":"three-digit house number","expected":"123416789234","passed":false},{"actual":"123416789450","check":"four-digit house number","expected":"123416789676","passed":false},{"actual":"123416789072","check":"one-digit house number is padded","expected":"123416789072","passed":true},{"actual":"123416789991","check":"no house digits uses the default","expected":"123416789991","passed":true},{"actual":"123416789126","check":"hyphenated house number stops at the hyphen","expected":"123416789126","passed":true},{"actual":"123419","check":"five-digit code has no delivery point","expected":"123419","passed":true},{"actual":"190000000307","check":"digit sum already a multiple of ten","expected":"190000000000","passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"three-digit house number\", \"actual\": \"123416789126\", \"expected\": \"123416789234\", \"passed\": false}, {\"check\": \"four-digit house number\", \"actual\": \"123416789450\", \"expected\": \"123416789676\", \"passed\": false}, {\"check\": \"one-digit house number is padded\", \"actual\": \"123416789072\", \"expected\": \"123416789072\", \"passed\": true}, {\"check\": \"no house digits uses the default\", \"actual\": \"123416789991\", \"expected\": \"123416789991\", \"passed\": true}, {\"check\": \"hyphenated house number stops at the hyphen\", \"actual\": \"123416789126\", \"expected\": \"123416789126\", \"passed\": true}, {\"check\": \"five-digit code has no delivery point\", \"actual\": \"123419\", \"expected\": \"123419\", \"passed\": true}, {\"check\": \"digit sum already a multiple of ten\", \"actual\": \"190000000307\", \"expected\": \"190000000000\", \"passed\": false}], \"passed\": false}\n"},"fixed":{"elapsed_ms":37.538,"exit_code":0,"observations":[{"actual":"123416789234","check":"three-digit house number","expected":"123416789234","passed":true},{"actual":"123416789676","check":"four-digit house number","expected":"123416789676","passed":true},{"actual":"123416789072","check":"one-digit house number is padded","expected":"123416789072","passed":true},{"actual":"123416789991","check":"no house digits uses the default","expected":"123416789991","passed":true},{"actual":"123416789126","check":"hyphenated house number stops at the hyphen","expected":"123416789126","passed":true},{"actual":"123419","check":"five-digit code has no delivery point","expected":"123419","passed":true},{"actual":"190000000000","check":"digit sum already a multiple of ten","expected":"190000000000","passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"three-digit house number\", \"actual\": \"123416789234\", \"expected\": \"123416789234\", \"passed\": true}, {\"check\": \"four-digit house number\", \"actual\": \"123416789676\", \"expected\": \"123416789676\", \"passed\": true}, {\"check\": \"one-digit house number is padded\", \"actual\": \"123416789072\", \"expected\": \"123416789072\", \"passed\": true}, {\"check\": \"no house digits uses the default\", \"actual\": \"123416789991\", \"expected\": \"123416789991\", \"passed\": true}, {\"check\": \"hyphenated house number stops at the hyphen\", \"actual\": \"123416789126\", \"expected\": \"123416789126\", \"passed\": true}, {\"check\": \"five-digit code has no delivery point\", \"actual\": \"123419\", \"expected\": \"123419\", \"passed\": true}, {\"check\": \"digit sum already a multiple of ten\", \"actual\": \"190000000000\", \"expected\": \"190000000000\", \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}