FAILURE MAP
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FA-83541 / Card game rule engines / Open access

Sub-runs inside a longer run are also scored · case 01

A four-card run also scores its two three-card sub-runs.

Verified by executionVariant 1 · 8 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The run loop does not stop after the longest run length.

VERIFIED REPAIR

Score only the longest run length found.

Unsuccessful approach: Scoring the length once ignores double and triple runs.

Case contract

Input [four_card_hand, starter, is_crib]. Fifteens (any 2-5 cards, A=1, T/J/Q/K=10) score 2; each pair 2; runs score their length for every distinct combination of the longest run length; a four-card hand flush scores 4 (+1 with the starter) but the crib scores only a five-card flush; a hand jack matching the starter suit scores 1. Return the total.

Why this case matters

Card-game engines, scoring apps and online tables apply this rule automatically on every hand.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import itertools
N = 1
observations = []
def solve(x):
    hand, starter, crib = x
    order = 'A23456789TJQK'
    cards = hand + [starter]
    def val(c):
        return min(order.index(c[0]) + 1, 10)
    score = 0
    for k in range(2, 6):
        for combo in itertools.combinations(cards, k):
            if sum(val(c) for c in combo) == 15:
                score += 2
    for a, b in itertools.combinations(cards, 2):
        if a[0] == b[0]:
            score += 2
    ranks = sorted(order.index(c[0]) for c in cards)
    for size in (5, 4, 3):
        runs = 0
        for combo in itertools.combinations(ranks, size):
            if all(combo[i + 1] == combo[i] + 1 for i in range(size - 1)):
                runs += 1
        if runs:
            score += runs * size
    suits = [c[1] for c in hand]
    if len(set(suits)) == 1:
        if starter[1] == suits[0]:
            score += 5
        elif not crib:
            score += 4
    for c in hand:
        if c[0] == 'J' and c[1] == starter[1]:
            score += 1
    return score
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[[[['AC', '9C', '4C', 'TC'], '5S', True], 6], [[['KD', 'AH', '4S', '8D'], 'QH', False], 4], [[['3C', '3S', '4S', '5H'], '2D', False], 12], [[['5H', '9S', '6S', '2S'], 'AH', False], 4], [[['3S', '3H', '5H', 'JH'], 'QS', False], 6], [[['4C', 'QC', 'AC', '6C'], '5D', True], 9], [[['AD', 'AH', '2S', '3H'], 'KC', False], 12], [[['6H', '6D', '7S', '8H'], 'JD', False], 10]], [[[['6S', '8D', 'JD', '9C'], '6D', False], 7], [[['4S', '5D', '9D', 'TC'], 'QH', True], 4], [[['5H', 'KC', '2H', '3S'], '6H', True], 4], [[['9H', '7H', 'QH', 'TH'], 'JH', False], 9], [[['2C', '2S', '3S', '4H'], 'KD', False], 12], [[['4S', '3S', '9S', 'TD'], '7C', False], 0], [[['4C', '4S', '5S', '6H'], '3D', True], 14], [[['KH', '9S', 'JS', 'JD'], 'QC', False], 8]], [[[['3H', 'QS', '3C', '6S'], '8D', False], 2], [[['JH', '9H', '9S', 'TD'], '3H', False], 9], [[['6C', '2C', '7C', 'AC'], '4H', True], 2], [[['4D', 'AS', '7H', 'QD'], '9S', False], 2], [[['6S', '5S', 'QS', '8C'], 'AC', False], 4], [[['8S', 'QS', 'TH', '9C'], 'QC', False], 5], [[['QS', 'KC', 'JC', '6H'], 'TH', False], 4], [[['AC', 'AH', '2S', '3H'], 'AD', False], 15]], [[[['AD', 'AH', '2S', '3H'], 'KC', False], 12], [[['AS', '9S', 'TS', '2S'], '4C', False], 8], [[['TD', 'KS', 'TH', 'TS'], 'JC', False], 6], [[['KS', '5D', '3H', '8D'], 'KD', True], 6], [[['2S', '8S', 'TC', 'JS'], 'QH', False], 3], [[['9H', '7S', 'QH', '5H'], '3D', False], 4], [[['KH', '3C', '5H', '5C'], '8S', False], 6], [[['3H', '4D', '6D', 'AS'], '5S', False], 8]], [[[['8D', '8C', '9S', 'TH'], 'AH', True], 8], [[['2H', '5H', 'AC', '3S'], '8C', False], 5], [[['AD', '4S', '9D', '4H'], 'TH', False], 6], [[['9S', '9C', 'JH', 'KS'], '3H', False], 3], [[['KD', 'TC', 'QS', '4D'], 'TH', True], 2], [[['QD', '8S', 'JC', '5H'], '6C', False], 5], [[['6H', '6D', '7S', '8H'], 'JD', False], 10], [[['5S', 'TD', 'JC', 'QH'], 'KS', False], 12]]]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check("hand score case %d" % i, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
hand score case 066Passed
hand score case 144Passed
hand score case 22412Failed
hand score case 344Passed
hand score case 466Passed
hand score case 599Passed
hand score case 61212Passed
hand score case 71010Passed

SHA-256 / dbba51ea489467afe08aff7f8eac5d049c6c38a4e53b2065cde7ec36c245a8d1

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import itertools
N = 1
observations = []
def solve(x):
    hand, starter, crib = x
    order = 'A23456789TJQK'
    cards = hand + [starter]
    def val(c):
        return min(order.index(c[0]) + 1, 10)
    score = 0
    for k in range(2, 6):
        for combo in itertools.combinations(cards, k):
            if sum(val(c) for c in combo) == 15:
                score += 2
    for a, b in itertools.combinations(cards, 2):
        if a[0] == b[0]:
            score += 2
    ranks = sorted(order.index(c[0]) for c in cards)
    for size in (5, 4, 3):
        runs = 0
        for combo in itertools.combinations(ranks, size):
            if all(combo[i + 1] == combo[i] + 1 for i in range(size - 1)):
                runs += 1
        if runs:
            score += size
            break
    suits = [c[1] for c in hand]
    if len(set(suits)) == 1:
        if starter[1] == suits[0]:
            score += 5
        elif not crib:
            score += 4
    for c in hand:
        if c[0] == 'J' and c[1] == starter[1]:
            score += 1
    return score
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[[[['AC', '9C', '4C', 'TC'], '5S', True], 6], [[['KD', 'AH', '4S', '8D'], 'QH', False], 4], [[['3C', '3S', '4S', '5H'], '2D', False], 12], [[['5H', '9S', '6S', '2S'], 'AH', False], 4], [[['3S', '3H', '5H', 'JH'], 'QS', False], 6], [[['4C', 'QC', 'AC', '6C'], '5D', True], 9], [[['AD', 'AH', '2S', '3H'], 'KC', False], 12], [[['6H', '6D', '7S', '8H'], 'JD', False], 10]], [[[['6S', '8D', 'JD', '9C'], '6D', False], 7], [[['4S', '5D', '9D', 'TC'], 'QH', True], 4], [[['5H', 'KC', '2H', '3S'], '6H', True], 4], [[['9H', '7H', 'QH', 'TH'], 'JH', False], 9], [[['2C', '2S', '3S', '4H'], 'KD', False], 12], [[['4S', '3S', '9S', 'TD'], '7C', False], 0], [[['4C', '4S', '5S', '6H'], '3D', True], 14], [[['KH', '9S', 'JS', 'JD'], 'QC', False], 8]], [[[['3H', 'QS', '3C', '6S'], '8D', False], 2], [[['JH', '9H', '9S', 'TD'], '3H', False], 9], [[['6C', '2C', '7C', 'AC'], '4H', True], 2], [[['4D', 'AS', '7H', 'QD'], '9S', False], 2], [[['6S', '5S', 'QS', '8C'], 'AC', False], 4], [[['8S', 'QS', 'TH', '9C'], 'QC', False], 5], [[['QS', 'KC', 'JC', '6H'], 'TH', False], 4], [[['AC', 'AH', '2S', '3H'], 'AD', False], 15]], [[[['AD', 'AH', '2S', '3H'], 'KC', False], 12], [[['AS', '9S', 'TS', '2S'], '4C', False], 8], [[['TD', 'KS', 'TH', 'TS'], 'JC', False], 6], [[['KS', '5D', '3H', '8D'], 'KD', True], 6], [[['2S', '8S', 'TC', 'JS'], 'QH', False], 3], [[['9H', '7S', 'QH', '5H'], '3D', False], 4], [[['KH', '3C', '5H', '5C'], '8S', False], 6], [[['3H', '4D', '6D', 'AS'], '5S', False], 8]], [[[['8D', '8C', '9S', 'TH'], 'AH', True], 8], [[['2H', '5H', 'AC', '3S'], '8C', False], 5], [[['AD', '4S', '9D', '4H'], 'TH', False], 6], [[['9S', '9C', 'JH', 'KS'], '3H', False], 3], [[['KD', 'TC', 'QS', '4D'], 'TH', True], 2], [[['QD', '8S', 'JC', '5H'], '6C', False], 5], [[['6H', '6D', '7S', '8H'], 'JD', False], 10], [[['5S', 'TD', 'JC', 'QH'], 'KS', False], 12]]]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check("hand score case %d" % i, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
hand score case 066Passed
hand score case 144Passed
hand score case 2812Failed
hand score case 344Passed
hand score case 466Passed
hand score case 599Passed
hand score case 6912Failed
hand score case 7710Failed

SHA-256 / b1f94fa4940068afba72f4ebcf0e91aaa1595e4453d31bfd7460d59fc8662f74

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json
import itertools
N = 1
observations = []
def solve(x):
    hand, starter, crib = x
    order = 'A23456789TJQK'
    cards = hand + [starter]
    def val(c):
        return min(order.index(c[0]) + 1, 10)
    score = 0
    for k in range(2, 6):
        for combo in itertools.combinations(cards, k):
            if sum(val(c) for c in combo) == 15:
                score += 2
    for a, b in itertools.combinations(cards, 2):
        if a[0] == b[0]:
            score += 2
    ranks = sorted(order.index(c[0]) for c in cards)
    for size in (5, 4, 3):
        runs = 0
        for combo in itertools.combinations(ranks, size):
            if all(combo[i + 1] == combo[i] + 1 for i in range(size - 1)):
                runs += 1
        if runs:
            score += runs * size
            break
    suits = [c[1] for c in hand]
    if len(set(suits)) == 1:
        if starter[1] == suits[0]:
            score += 5
        elif not crib:
            score += 4
    for c in hand:
        if c[0] == 'J' and c[1] == starter[1]:
            score += 1
    return score
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[[[['AC', '9C', '4C', 'TC'], '5S', True], 6], [[['KD', 'AH', '4S', '8D'], 'QH', False], 4], [[['3C', '3S', '4S', '5H'], '2D', False], 12], [[['5H', '9S', '6S', '2S'], 'AH', False], 4], [[['3S', '3H', '5H', 'JH'], 'QS', False], 6], [[['4C', 'QC', 'AC', '6C'], '5D', True], 9], [[['AD', 'AH', '2S', '3H'], 'KC', False], 12], [[['6H', '6D', '7S', '8H'], 'JD', False], 10]], [[[['6S', '8D', 'JD', '9C'], '6D', False], 7], [[['4S', '5D', '9D', 'TC'], 'QH', True], 4], [[['5H', 'KC', '2H', '3S'], '6H', True], 4], [[['9H', '7H', 'QH', 'TH'], 'JH', False], 9], [[['2C', '2S', '3S', '4H'], 'KD', False], 12], [[['4S', '3S', '9S', 'TD'], '7C', False], 0], [[['4C', '4S', '5S', '6H'], '3D', True], 14], [[['KH', '9S', 'JS', 'JD'], 'QC', False], 8]], [[[['3H', 'QS', '3C', '6S'], '8D', False], 2], [[['JH', '9H', '9S', 'TD'], '3H', False], 9], [[['6C', '2C', '7C', 'AC'], '4H', True], 2], [[['4D', 'AS', '7H', 'QD'], '9S', False], 2], [[['6S', '5S', 'QS', '8C'], 'AC', False], 4], [[['8S', 'QS', 'TH', '9C'], 'QC', False], 5], [[['QS', 'KC', 'JC', '6H'], 'TH', False], 4], [[['AC', 'AH', '2S', '3H'], 'AD', False], 15]], [[[['AD', 'AH', '2S', '3H'], 'KC', False], 12], [[['AS', '9S', 'TS', '2S'], '4C', False], 8], [[['TD', 'KS', 'TH', 'TS'], 'JC', False], 6], [[['KS', '5D', '3H', '8D'], 'KD', True], 6], [[['2S', '8S', 'TC', 'JS'], 'QH', False], 3], [[['9H', '7S', 'QH', '5H'], '3D', False], 4], [[['KH', '3C', '5H', '5C'], '8S', False], 6], [[['3H', '4D', '6D', 'AS'], '5S', False], 8]], [[[['8D', '8C', '9S', 'TH'], 'AH', True], 8], [[['2H', '5H', 'AC', '3S'], '8C', False], 5], [[['AD', '4S', '9D', '4H'], 'TH', False], 6], [[['9S', '9C', 'JH', 'KS'], '3H', False], 3], [[['KD', 'TC', 'QS', '4D'], 'TH', True], 2], [[['QD', '8S', 'JC', '5H'], '6C', False], 5], [[['6H', '6D', '7S', '8H'], 'JD', False], 10], [[['5S', 'TD', 'JC', 'QH'], 'KS', False], 12]]]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check("hand score case %d" % i, solve(args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
hand score case 066Passed
hand score case 144Passed
hand score case 21212Passed
hand score case 344Passed
hand score case 466Passed
hand score case 599Passed
hand score case 61212Passed
hand score case 71010Passed

SHA-256 / 1c6977447567fff117e9fadeb944b6c6903194b80f6858d88216000e1f79b069

Verification & scope

A bounded toy rule contract stated explicitly in the contract field; cards are two-character codes (rank, suit). Not a complete implementation of any published rulebook or casino table rules. 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.

Observations recorded using Python 3.12.14 at 2026-09-29T14:50:22.593537+00:00.

Case digest / df3976e49cd628056d6d68e08c161606ef85727602c922d6e4e9a180129d241d