{"abstract":"Every package code scans as a different product number.","category":"Barcode symbology encoding","checks":8,"contract":"Encode an integer 3..131070 as a one-track Pharmacode: repeatedly, an even value adds a wide bar and becomes (n - 2) / 2, an odd value adds a narrow bar and becomes (n - 1) / 2, until zero; bars are read in the reverse order of generation (left to right). Width: narrow 1, wide 3, spaces 2 between bars. Return [pattern, width] or None outside the range.","evaluation_group":"w2-barcode-symbology-encoding-pharmacode-bars","failed_approach":"Testing divisibility by four misclassifies values that are 2 mod 4.","family":"w2-barcode-symbology-encoding-pharmacode-bars-parity-rule","id":"FA-79826","implementations":{"attempt":{"sha256":"954b66b43c43a905fe2c1c3fced2c5f575bb398c2e2e9f14170c4558aef07659","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(n):\n    if not isinstance(n, int) or n < 3 or n > 131070:\n        return None\n    bars = []\n    while n > 0:\n        if n % 4 == 0:\n            bars.append('w')\n            n = (n - 2) // 2\n        else:\n            bars.append('n')\n            n = (n - 1) // 2\n    bars.reverse()\n    width = sum(3 if b == 'w' else 1 for b in bars) + 2 * (len(bars) - 1)\n    return [''.join(bars), width]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [[[34, ['nnnww', 17]], [120, ['wwwnnw', 24]], [1, None], [2, None], [131071, None], [0, None], [-5, None], [306, ['nnwwnnww', 30]]], [[6, ['ww', 8]], [146, ['nnwnnww', 25]], [2, None], [131071, None], [0, None], [-5, None], [1, None], [85, ['nwnwwn', 22]]], [[142, ['nnnwwww', 27]], [86, ['nwnwww', 24]], [131071, None], [0, None], [-5, None], [1, None], [2, None], [396, ['wnnnwwnw', 30]]], [[229, ['wwnnwwn', 27]], [157, ['nnwwwwn', 27]], [240, ['wwwnnnw', 27]], [0, None], [-5, None], [1, None], [2, None], [143, ['nnwnnnn', 21]]], [[157, ['nnwwwwn', 27]], [228, ['wwnnwnw', 27]], [242, ['wwwnnww', 29]], [-5, None], [1, None], [2, None], [131071, None], [225, ['wwnnnwn', 25]]]]\nlabels = [\"regression: even value bar type\", \"repair trap\", \"combined fault\", \"control\", \"control\", \"boundary\", \"boundary\", \"control\"]\nfor i, (args, expected) in enumerate(fixtures[N-1]):\n    check(\"%s %d\" % (labels[i % len(labels)], i), 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":"f199fbfaab66d67c75cef7cd33e64da4311c8515fa6e6888db753164c9ef958b","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(n):\n    if not isinstance(n, int) or n < 3 or n > 131070:\n        return None\n    bars = []\n    while n > 0:\n        if n % 2 == 1:\n            bars.append('w')\n            n = (n - 2) // 2\n        else:\n            bars.append('n')\n            n = (n - 1) // 2\n    bars.reverse()\n    width = sum(3 if b == 'w' else 1 for b in bars) + 2 * (len(bars) - 1)\n    return [''.join(bars), width]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [[[34, ['nnnww', 17]], [120, ['wwwnnw', 24]], [1, None], [2, None], [131071, None], [0, None], [-5, None], [306, ['nnwwnnww', 30]]], [[6, ['ww', 8]], [146, ['nnwnnww', 25]], [2, None], [131071, None], [0, None], [-5, None], [1, None], [85, ['nwnwwn', 22]]], [[142, ['nnnwwww', 27]], [86, ['nwnwww', 24]], [131071, None], [0, None], [-5, None], [1, None], [2, None], [396, ['wnnnwwnw', 30]]], [[229, ['wwnnwwn', 27]], [157, ['nnwwwwn', 27]], [240, ['wwwnnnw', 27]], [0, None], [-5, None], [1, None], [2, None], [143, ['nnwnnnn', 21]]], [[157, ['nnwwwwn', 27]], [228, ['wwnnwnw', 27]], [242, ['wwwnnww', 29]], [-5, None], [1, None], [2, None], [131071, None], [225, ['wwnnnwn', 25]]]]\nlabels = [\"regression: even value bar type\", \"repair trap\", \"combined fault\", \"control\", \"control\", \"boundary\", \"boundary\", \"control\"]\nfor i, (args, expected) in enumerate(fixtures[N-1]):\n    check(\"%s %d\" % (labels[i % len(labels)], i), 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"},"fixed":{"sha256":"5f4f0c2275245a342e80b10caaa5ba8e362655408c6f9fa0ae916dcb2c816f09","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(n):\n    if not isinstance(n, int) or n < 3 or n > 131070:\n        return None\n    bars = []\n    while n > 0:\n        if n % 2 == 0:\n            bars.append('w')\n            n = (n - 2) // 2\n        else:\n            bars.append('n')\n            n = (n - 1) // 2\n    bars.reverse()\n    width = sum(3 if b == 'w' else 1 for b in bars) + 2 * (len(bars) - 1)\n    return [''.join(bars), width]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [[[34, ['nnnww', 17]], [120, ['wwwnnw', 24]], [1, None], [2, None], [131071, None], [0, None], [-5, None], [306, ['nnwwnnww', 30]]], [[6, ['ww', 8]], [146, ['nnwnnww', 25]], [2, None], [131071, None], [0, None], [-5, None], [1, None], [85, ['nwnwwn', 22]]], [[142, ['nnnwwww', 27]], [86, ['nwnwww', 24]], [131071, None], [0, None], [-5, None], [1, None], [2, None], [396, ['wnnnwwnw', 30]]], [[229, ['wwnnwwn', 27]], [157, ['nnwwwwn', 27]], [240, ['wwwnnnw', 27]], [0, None], [-5, None], [1, None], [2, None], [143, ['nnwnnnn', 21]]], [[157, ['nnwwwwn', 27]], [228, ['wwnnwnw', 27]], [242, ['wwwnnww', 29]], [-5, None], [1, None], [2, None], [131071, None], [225, ['wwnnnwn', 25]]]]\nlabels = [\"regression: even value bar type\", \"repair trap\", \"combined fault\", \"control\", \"control\", \"boundary\", \"boundary\", \"control\"]\nfor i, (args, expected) in enumerate(fixtures[N-1]):\n    check(\"%s %d\" % (labels[i % len(labels)], i), 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 with a stipulated contract; it makes no claim of conformance to any published specification. 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-barcode-symbology-encoding-pharmacode-bars-parity-rule","generated_at":"2026-09-29T14:49:48.210266+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Retail, logistics, pharmacy and document workflows depend on encoders that produce exactly the module pattern, code-set switches, separators and quiet zones scanners expect; one misplaced module or separator makes a label unreadable or, worse, scan as different data.","repair":"Even values produce wide bars.","root_cause":"The parity test is inverted, so odd values produce wide bars.","sha256":"126913fdb1fbf9ad4c6ffe0766278f2587dfcef2a6cac242be1d7a124f8bf71a","title":"Pharmacode assigns wide bars to odd values · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":40.584,"exit_code":1,"observations":[{"actual":["nnnwn",15],"check":"regression: even value bar type 0","expected":["nnnww",17],"passed":false},{"actual":["nnnnnw",18],"check":"repair trap 1","expected":["wwwnnw",24],"passed":false},{"actual":null,"check":"combined fault 2","expected":null,"passed":true},{"actual":null,"check":"control 3","expected":null,"passed":true},{"actual":null,"check":"control 4","expected":null,"passed":true},{"actual":null,"check":"boundary 5","expected":null,"passed":true},{"actual":null,"check":"boundary 6","expected":null,"passed":true},{"actual":["nnwnnnwn",26],"check":"control 7","expected":["nnwwnnww",30],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"regression: even value bar type 0\", \"actual\": [\"nnnwn\", 15], \"expected\": [\"nnnww\", 17], \"passed\": false}, {\"check\": \"repair trap 1\", \"actual\": [\"nnnnnw\", 18], \"expected\": [\"wwwnnw\", 24], \"passed\": false}, {\"check\": \"combined fault 2\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"control 3\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"control 4\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"boundary 5\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"boundary 6\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"control 7\", \"actual\": [\"nnwnnnwn\", 26], \"expected\": [\"nnwwnnww\", 30], \"passed\": false}], \"passed\": false}\n"},"broken":{"elapsed_ms":41.029,"exit_code":1,"observations":[{"actual":["nwnn",12],"check":"regression: even value bar type 0","expected":["nnnww",17],"passed":false},{"actual":["wwwnwn",24],"check":"repair trap 1","expected":["wwwnnw",24],"passed":false},{"actual":null,"check":"combined fault 2","expected":null,"passed":true},{"actual":null,"check":"control 3","expected":null,"passed":true},{"actual":null,"check":"control 4","expected":null,"passed":true},{"actual":null,"check":"boundary 5","expected":null,"passed":true},{"actual":null,"check":"boundary 6","expected":null,"passed":true},{"actual":["nwwnwnn",25],"check":"control 7","expected":["nnwwnnww",30],"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"regression: even value bar type 0\", \"actual\": [\"nwnn\", 12], \"expected\": [\"nnnww\", 17], \"passed\": false}, {\"check\": \"repair trap 1\", \"actual\": [\"wwwnwn\", 24], \"expected\": [\"wwwnnw\", 24], \"passed\": false}, {\"check\": \"combined fault 2\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"control 3\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"control 4\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"boundary 5\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"boundary 6\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"control 7\", \"actual\": [\"nwwnwnn\", 25], \"expected\": [\"nnwwnnww\", 30], \"passed\": false}], \"passed\": false}\n"},"fixed":{"elapsed_ms":40.507,"exit_code":0,"observations":[{"actual":["nnnww",17],"check":"regression: even value bar type 0","expected":["nnnww",17],"passed":true},{"actual":["wwwnnw",24],"check":"repair trap 1","expected":["wwwnnw",24],"passed":true},{"actual":null,"check":"combined fault 2","expected":null,"passed":true},{"actual":null,"check":"control 3","expected":null,"passed":true},{"actual":null,"check":"control 4","expected":null,"passed":true},{"actual":null,"check":"boundary 5","expected":null,"passed":true},{"actual":null,"check":"boundary 6","expected":null,"passed":true},{"actual":["nnwwnnww",30],"check":"control 7","expected":["nnwwnnww",30],"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"regression: even value bar type 0\", \"actual\": [\"nnnww\", 17], \"expected\": [\"nnnww\", 17], \"passed\": true}, {\"check\": \"repair trap 1\", \"actual\": [\"wwwnnw\", 24], \"expected\": [\"wwwnnw\", 24], \"passed\": true}, {\"check\": \"combined fault 2\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"control 3\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"control 4\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"boundary 5\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"boundary 6\", \"actual\": null, \"expected\": null, \"passed\": true}, {\"check\": \"control 7\", \"actual\": [\"nnwwnnww\", 30], \"expected\": [\"nnwwnnww\", 30], \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}