{"abstract":"The current sample is excluded from each prefix.","category":"Discrete calculus","checks":4,"contract":"Integer sample values and compatible sample-array lengths. Rational results are reduced Fraction strings; spacing is positive unless explicitly stated otherwise. Prefix sums inclusive. Exact operational definition: list(itertools.accumulate(values))","evaluation_group":"model-14cccdb34b5be4ad","failed_approach":"Suffix totals reverse the accumulation direction.","family":"xn-prefix-sums-inclusive","id":"FA-6361","implementations":{"attempt":{"sha256":"5decbf10f844b4950671a551b29cb698a9eb2622fbae4a44308a609b87f9709a","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nimport calendar\nimport statistics\nimport itertools\nfrom fractions import Fraction\nfrom datetime import date, datetime, timedelta, timezone\nfrom decimal import Decimal, ROUND_HALF_UP, ROUND_DOWN, ROUND_CEILING, ROUND_FLOOR\n\nN = 1\nobservations = []\ndef solve(values):\n    return [sum(values[i:]) for i in range(len(values))]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1: ([1, 2, 3],)', solve(*([1, 2, 3],)), [1, 3, 6])\ncheck('fixture 2: ([2, -2, 4],)', solve(*([2, -2, 4],)), [2, 0, 4])\ncheck('fixture 3: ([5],)', solve(*([5],)), [5])\ncheck('fixture 4: ([],)', solve(*([],)), [])\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":"0ab418788b75b7efe3c48acd8af13a2f9754dcd3f78c809f080fca3afe485acb","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nimport calendar\nimport statistics\nimport itertools\nfrom fractions import Fraction\nfrom datetime import date, datetime, timedelta, timezone\nfrom decimal import Decimal, ROUND_HALF_UP, ROUND_DOWN, ROUND_CEILING, ROUND_FLOOR\n\nN = 1\nobservations = []\ndef solve(values):\n    return [sum(values[:i]) for i in range(len(values))]\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1: ([1, 2, 3],)', solve(*([1, 2, 3],)), [1, 3, 6])\ncheck('fixture 2: ([2, -2, 4],)', solve(*([2, -2, 4],)), [2, 0, 4])\ncheck('fixture 3: ([5],)', solve(*([5],)), [5])\ncheck('fixture 4: ([],)', solve(*([],)), [])\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":"6a5304898063427b4fd857ac66e221bb626d73111326f42ac9f151266afa61a7","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nimport calendar\nimport statistics\nimport itertools\nfrom fractions import Fraction\nfrom datetime import date, datetime, timedelta, timezone\nfrom decimal import Decimal, ROUND_HALF_UP, ROUND_DOWN, ROUND_CEILING, ROUND_FLOOR\n\nN = 1\nobservations = []\ndef solve(values):\n    return list(itertools.accumulate(values))\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncheck('fixture 1: ([1, 2, 3],)', solve(*([1, 2, 3],)), [1, 3, 6])\ncheck('fixture 2: ([2, -2, 4],)', solve(*([2, -2, 4],)), [2, 0, 4])\ncheck('fixture 3: ([5],)', solve(*([5],)), [5])\ncheck('fixture 4: ([],)', solve(*([],)), [])\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":" 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":"xn-prefix-sums-inclusive","generated_at":"2026-09-29T14:38:00.651574+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Small exact fixtures expose this error without platform timing, external services, or probabilistic observations. Discrete calculus results depend on the stated convention.","repair":"Apply the specified mathematical contract directly, preserving all terms and boundary cases: return list(itertools.accumulate(values))","root_cause":"The current sample is excluded from each prefix.","sha256":"53ede76122d65ae8d3fd5cb6cd775eae5d2cc95e97b38f51cd24fd7d67f395e5","title":"Prefix sums inclusive · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verification":{"attempt":{"elapsed_ms":50.436,"exit_code":1,"observations":[{"actual":[6,5,3],"check":"fixture 1: ([1, 2, 3],)","expected":[1,3,6],"passed":false},{"actual":[4,2,4],"check":"fixture 2: ([2, -2, 4],)","expected":[2,0,4],"passed":false},{"actual":[5],"check":"fixture 3: ([5],)","expected":[5],"passed":true},{"actual":[],"check":"fixture 4: ([],)","expected":[],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1: ([1, 2, 3],)\", \"actual\": [6, 5, 3], \"expected\": [1, 3, 6], \"passed\": false}, {\"check\": \"fixture 2: ([2, -2, 4],)\", \"actual\": [4, 2, 4], \"expected\": [2, 0, 4], \"passed\": false}, {\"check\": \"fixture 3: ([5],)\", \"actual\": [5], \"expected\": [5], \"passed\": true}, {\"check\": \"fixture 4: ([],)\", \"actual\": [], \"expected\": [], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":66.486,"exit_code":1,"observations":[{"actual":[0,1,3],"check":"fixture 1: ([1, 2, 3],)","expected":[1,3,6],"passed":false},{"actual":[0,2,0],"check":"fixture 2: ([2, -2, 4],)","expected":[2,0,4],"passed":false},{"actual":[0],"check":"fixture 3: ([5],)","expected":[5],"passed":false},{"actual":[],"check":"fixture 4: ([],)","expected":[],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1: ([1, 2, 3],)\", \"actual\": [0, 1, 3], \"expected\": [1, 3, 6], \"passed\": false}, {\"check\": \"fixture 2: ([2, -2, 4],)\", \"actual\": [0, 2, 0], \"expected\": [2, 0, 4], \"passed\": false}, {\"check\": \"fixture 3: ([5],)\", \"actual\": [0], \"expected\": [5], \"passed\": false}, {\"check\": \"fixture 4: ([],)\", \"actual\": [], \"expected\": [], \"passed\": true}], \"passed\": false}\n"},"fixed":{"elapsed_ms":43.712,"exit_code":0,"observations":[{"actual":[1,3,6],"check":"fixture 1: ([1, 2, 3],)","expected":[1,3,6],"passed":true},{"actual":[2,0,4],"check":"fixture 2: ([2, -2, 4],)","expected":[2,0,4],"passed":true},{"actual":[5],"check":"fixture 3: ([5],)","expected":[5],"passed":true},{"actual":[],"check":"fixture 4: ([],)","expected":[],"passed":true}],"passed":true,"stderr":"","stdout":"{\"observations\": [{\"check\": \"fixture 1: ([1, 2, 3],)\", \"actual\": [1, 3, 6], \"expected\": [1, 3, 6], \"passed\": true}, {\"check\": \"fixture 2: ([2, -2, 4],)\", \"actual\": [2, 0, 4], \"expected\": [2, 0, 4], \"passed\": true}, {\"check\": \"fixture 3: ([5],)\", \"actual\": [5], \"expected\": [5], \"passed\": true}, {\"check\": \"fixture 4: ([],)\", \"actual\": [], \"expected\": [], \"passed\": true}], \"passed\": true}\n"}},"verified":true,"visibility":"public"}