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FA-68611 / Toll and parking fee computation / Open access

Pay-by-plate invoice and tag discount: exempt trips fall through to plate billing · case 01

Pay-by-plate invoice and tag discount returns a wrong result when exempt trips fall through to plate billing.

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

ROOT CAUSE

Exempt trips are billed as plate trips with surcharge and invoice.

THE FAILURE

Exempt trips are billed as plate trips with surcharge and invoice.

Unsuccessful approach: Zeroing the base still opens a plate invoice and its fee for an exempt vehicle.

Case contract

Input {trips: [[day (0-based), base cents, tag|plate|exempt]], plate_surcharge_pct, tag_discount_pct, invoice_fee, cycle_days}. Exempt trips are ignored. Tag trips pay base minus a discount floored to cents. Plate trips pay base plus a surcharge rounded up to cents and are grouped into invoices by billing period day // cycle_days; each invoice adds one invoice_fee to the plate total. Return {tag, plate, invoices}.

Why this case matters

Fee engines bill customers in integer cents; a wrong boundary, rounding stage or cap scope silently over- or under-charges.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(x):
    tag = plate = 0
    periods = set()
    for day, base, method in x['trips']:
        if method == 'exempt':
            pass
        if method == 'tag':
            tag += base - base * x['tag_discount_pct'] // 100
        else:
            plate += base + -(-base * x['plate_surcharge_pct'] // 100)
            periods.add(day // x['cycle_days'])
    fees = len(periods) * x['invoice_fee']
    return {'tag': tag, 'plate': plate + fees, 'invoices': len(periods)}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[({'trips': [[19, 525, 'tag']], 'plate_surcharge_pct': 25, 'tag_discount_pct': 15, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 447, 'plate': 0, 'invoices': 0}), ({'trips': [[3, 410, 'exempt'], [4, 410, 'tag']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 10, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 369, 'plate': 0, 'invoices': 0}), ({'trips': [[14, 175, 'tag'], [8, 333, 'plate'], [31, 333, 'tag'], [34, 333, 'tag'], [85, 525, 'tag']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 5, 'invoice_fee': 150, 'cycle_days': 30}, {'tag': 1300, 'plate': 600, 'invoices': 1}), ({'trips': [[46, 250, 'plate'], [36, 175, 'tag'], [84, 250, 'plate']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 15, 'invoice_fee': 150, 'cycle_days': 31}, {'tag': 149, 'plate': 976, 'invoices': 2}), ({'trips': [[28, 410, 'exempt'], [41, 333, 'tag']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 15, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 284, 'plate': 0, 'invoices': 0}), ({'trips': [[29, 250, 'plate'], [30, 250, 'plate'], [5, 333, 'tag']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 15, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 284, 'plate': 1076, 'invoices': 2}), ({'trips': [[86, 525, 'exempt'], [43, 525, 'plate'], [12, 410, 'plate'], [69, 525, 'plate'], [35, 410, 'plate']], 'plate_surcharge_pct': 25, 'tag_discount_pct': 10, 'invoice_fee': 200, 'cycle_days': 31}, {'tag': 0, 'plate': 2940, 'invoices': 3}), ({'trips': [[46, 250, 'exempt'], [13, 410, 'tag'], [29, 333, 'plate'], [27, 525, 'exempt']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 10, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 369, 'plate': 650, 'invoices': 1})], [({'trips': [[34, 410, 'plate'], [42, 410, 'tag'], [69, 525, 'plate'], [4, 525, 'tag'], [11, 250, 'exempt'], [87, 525, 'tag']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 10, 'invoice_fee': 400, 'cycle_days': 30}, {'tag': 1315, 'plate': 2063, 'invoices': 2}), ({'trips': [[77, 250, 'plate'], [50, 175, 'plate'], [14, 175, 'tag'], [81, 250, 'plate'], [89, 333, 'tag'], [61, 250, 'tag'], [19, 333, 'tag'], [9, 333, 'tag']], 'plate_surcharge_pct': 25, 'tag_discount_pct': 5, 'invoice_fee': 150, 'cycle_days': 31}, {'tag': 1356, 'plate': 1145, 'invoices': 2}), ({'trips': [[33, 333, 'plate']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 10, 'invoice_fee': 200, 'cycle_days': 31}, {'tag': 0, 'plate': 650, 'invoices': 1}), ({'trips': [[76, 250, 'tag'], [39, 175, 'plate'], [95, 175, 'plate'], [20, 333, 'plate'], [78, 410, 'exempt'], [59, 250, 'plate'], [88, 410, 'tag'], [5, 175, 'plate']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 5, 'invoice_fee': 150, 'cycle_days': 31}, {'tag': 628, 'plate': 1949, 'invoices': 3}), ({'trips': [[55, 410, 'exempt']], 'plate_surcharge_pct': 25, 'tag_discount_pct': 5, 'invoice_fee': 200, 'cycle_days': 31}, {'tag': 0, 'plate': 0, 'invoices': 0}), ({'trips': [[3, 410, 'exempt'], [4, 410, 'tag']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 10, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 369, 'plate': 0, 'invoices': 0}), ({'trips': [[19, 525, 'plate'], [51, 410, 'plate']], 'plate_surcharge_pct': 25, 'tag_discount_pct': 15, 'invoice_fee': 400, 'cycle_days': 31}, {'tag': 0, 'plate': 1970, 'invoices': 2}), ({'trips': [[29, 250, 'plate'], [30, 250, 'plate'], [5, 333, 'tag']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 15, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 284, 'plate': 1076, 'invoices': 2})], [({'trips': [[40, 410, 'tag'], [72, 250, 'exempt'], [22, 410, 'tag'], [1, 525, 'exempt'], [12, 410, 'plate'], [67, 525, 'plate'], [31, 410, 'tag']], 'plate_surcharge_pct': 25, 'tag_discount_pct': 5, 'invoice_fee': 150, 'cycle_days': 31}, {'tag': 1170, 'plate': 1470, 'invoices': 2}), ({'trips': [[3, 410, 'exempt'], [4, 410, 'tag']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 10, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 369, 'plate': 0, 'invoices': 0}), ({'trips': [[29, 250, 'plate'], [30, 250, 'plate'], [5, 333, 'tag']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 15, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 284, 'plate': 1076, 'invoices': 2}), ({'trips': [[52, 175, 'plate'], [89, 525, 'tag'], [15, 333, 'plate'], [70, 333, 'plate'], [65, 333, 'tag'], [45, 250, 'tag'], [80, 175, 'tag'], [82, 410, 'tag']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 10, 'invoice_fee': 150, 'cycle_days': 31}, {'tag': 1525, 'plate': 1713, 'invoices': 3}), ({'trips': [[12, 250, 'exempt'], [79, 175, 'plate'], [39, 175, 'plate'], [33, 175, 'plate'], [59, 525, 'tag']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 15, 'invoice_fee': 400, 'cycle_days': 31}, {'tag': 447, 'plate': 1589, 'invoices': 2}), ({'trips': [[69, 525, 'tag'], [7, 525, 'plate'], [83, 410, 'plate'], [84, 333, 'tag'], [1, 175, 'plate'], [52, 175, 'plate'], [0, 525, 'plate'], [33, 410, 'plate']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 10, 'invoice_fee': 150, 'cycle_days': 30}, {'tag': 773, 'plate': 3782, 'invoices': 3}), ({'trips': [[1, 525, 'plate'], [80, 333, 'tag'], [16, 250, 'tag'], [26, 525, 'plate'], [81, 410, 'tag'], [16, 525, 'plate'], [22, 250, 'plate']], 'plate_surcharge_pct': 25, 'tag_discount_pct': 5, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 945, 'plate': 2484, 'invoices': 1}), ({'trips': [[59, 410, 'plate']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 15, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 0, 'plate': 815, 'invoices': 1})], [({'trips': [[29, 250, 'plate'], [30, 250, 'plate'], [5, 333, 'tag']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 15, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 284, 'plate': 1076, 'invoices': 2}), ({'trips': [[64, 410, 'tag'], [37, 250, 'plate'], [70, 410, 'exempt'], [69, 333, 'plate'], [15, 250, 'tag']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 5, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 628, 'plate': 1188, 'invoices': 2}), ({'trips': [[39, 175, 'exempt'], [88, 250, 'exempt'], [26, 333, 'plate'], [38, 250, 'plate'], [87, 333, 'plate'], [91, 333, 'tag'], [95, 333, 'plate'], [21, 333, 'exempt']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 15, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 284, 'plate': 2675, 'invoices': 4}), ({'trips': [[89, 410, 'tag'], [63, 250, 'plate'], [89, 333, 'plate']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 10, 'invoice_fee': 150, 'cycle_days': 31}, {'tag': 369, 'plate': 1025, 'invoices': 1}), ({'trips': [[3, 410, 'exempt'], [4, 410, 'tag']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 10, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 369, 'plate': 0, 'invoices': 0}), ({'trips': [[45, 175, 'plate']], 'plate_surcharge_pct': 25, 'tag_discount_pct': 5, 'invoice_fee': 400, 'cycle_days': 31}, {'tag': 0, 'plate': 619, 'invoices': 1}), ({'trips': [[21, 333, 'tag'], [53, 175, 'tag']], 'plate_surcharge_pct': 25, 'tag_discount_pct': 10, 'invoice_fee': 400, 'cycle_days': 31}, {'tag': 458, 'plate': 0, 'invoices': 0}), ({'trips': [[16, 410, 'tag'], [38, 333, 'plate'], [40, 175, 'plate'], [91, 250, 'exempt'], [67, 250, 'tag']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 5, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 628, 'plate': 963, 'invoices': 1})], [({'trips': [[34, 175, 'plate'], [12, 175, 'plate'], [40, 250, 'plate'], [83, 525, 'tag'], [79, 250, 'plate']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 10, 'invoice_fee': 150, 'cycle_days': 30}, {'tag': 473, 'plate': 1726, 'invoices': 3}), ({'trips': [[23, 175, 'plate'], [66, 525, 'plate'], [52, 410, 'plate'], [73, 175, 'plate'], [39, 410, 'exempt'], [44, 250, 'tag'], [20, 333, 'tag'], [66, 410, 'exempt']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 5, 'invoice_fee': 400, 'cycle_days': 30}, {'tag': 555, 'plate': 3129, 'invoices': 3}), ({'trips': [[83, 175, 'exempt'], [80, 333, 'plate']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 10, 'invoice_fee': 400, 'cycle_days': 31}, {'tag': 0, 'plate': 900, 'invoices': 1}), ({'trips': [[3, 410, 'exempt'], [4, 410, 'tag']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 10, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 369, 'plate': 0, 'invoices': 0}), ({'trips': [[29, 250, 'plate'], [30, 250, 'plate'], [5, 333, 'tag']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 15, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 284, 'plate': 1076, 'invoices': 2}), ({'trips': [[67, 525, 'tag'], [87, 525, 'exempt'], [47, 525, 'tag'], [12, 250, 'tag'], [26, 250, 'exempt']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 5, 'invoice_fee': 400, 'cycle_days': 30}, {'tag': 1236, 'plate': 0, 'invoices': 0}), ({'trips': [[88, 175, 'tag']], 'plate_surcharge_pct': 25, 'tag_discount_pct': 5, 'invoice_fee': 400, 'cycle_days': 30}, {'tag': 167, 'plate': 0, 'invoices': 0}), ({'trips': [[92, 525, 'tag'], [74, 333, 'tag'], [73, 333, 'plate']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 10, 'invoice_fee': 200, 'cycle_days': 31}, {'tag': 773, 'plate': 700, 'invoices': 1})]]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check('fee oracle' + ' %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
fee oracle 0{'invoices': 0, 'plate': 0, 'tag': 447}{'invoices': 0, 'plate': 0, 'tag': 447}Passed
fee oracle 1{'invoices': 1, 'plate': 815, 'tag': 369}{'invoices': 0, 'plate': 0, 'tag': 369}Failed
fee oracle 2{'invoices': 1, 'plate': 600, 'tag': 1300}{'invoices': 1, 'plate': 600, 'tag': 1300}Passed
fee oracle 3{'invoices': 2, 'plate': 976, 'tag': 149}{'invoices': 2, 'plate': 976, 'tag': 149}Passed
fee oracle 4{'invoices': 1, 'plate': 754, 'tag': 284}{'invoices': 0, 'plate': 0, 'tag': 284}Failed
fee oracle 5{'invoices': 2, 'plate': 1076, 'tag': 284}{'invoices': 2, 'plate': 1076, 'tag': 284}Passed
fee oracle 6{'invoices': 3, 'plate': 3597, 'tag': 0}{'invoices': 3, 'plate': 2940, 'tag': 0}Failed
fee oracle 7{'invoices': 2, 'plate': 1897, 'tag': 369}{'invoices': 1, 'plate': 650, 'tag': 369}Failed

SHA-256 / 2fba38db69fb5fbf93f7289d9551f69abcb54122e290b6786f87a528933d43af

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(x):
    tag = plate = 0
    periods = set()
    for day, base, method in x['trips']:
        if method == 'exempt':
            base = 0
        if method == 'tag':
            tag += base - base * x['tag_discount_pct'] // 100
        else:
            plate += base + -(-base * x['plate_surcharge_pct'] // 100)
            periods.add(day // x['cycle_days'])
    fees = len(periods) * x['invoice_fee']
    return {'tag': tag, 'plate': plate + fees, 'invoices': len(periods)}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[({'trips': [[19, 525, 'tag']], 'plate_surcharge_pct': 25, 'tag_discount_pct': 15, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 447, 'plate': 0, 'invoices': 0}), ({'trips': [[3, 410, 'exempt'], [4, 410, 'tag']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 10, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 369, 'plate': 0, 'invoices': 0}), ({'trips': [[14, 175, 'tag'], [8, 333, 'plate'], [31, 333, 'tag'], [34, 333, 'tag'], [85, 525, 'tag']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 5, 'invoice_fee': 150, 'cycle_days': 30}, {'tag': 1300, 'plate': 600, 'invoices': 1}), ({'trips': [[46, 250, 'plate'], [36, 175, 'tag'], [84, 250, 'plate']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 15, 'invoice_fee': 150, 'cycle_days': 31}, {'tag': 149, 'plate': 976, 'invoices': 2}), ({'trips': [[28, 410, 'exempt'], [41, 333, 'tag']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 15, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 284, 'plate': 0, 'invoices': 0}), ({'trips': [[29, 250, 'plate'], [30, 250, 'plate'], [5, 333, 'tag']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 15, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 284, 'plate': 1076, 'invoices': 2}), ({'trips': [[86, 525, 'exempt'], [43, 525, 'plate'], [12, 410, 'plate'], [69, 525, 'plate'], [35, 410, 'plate']], 'plate_surcharge_pct': 25, 'tag_discount_pct': 10, 'invoice_fee': 200, 'cycle_days': 31}, {'tag': 0, 'plate': 2940, 'invoices': 3}), ({'trips': [[46, 250, 'exempt'], [13, 410, 'tag'], [29, 333, 'plate'], [27, 525, 'exempt']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 10, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 369, 'plate': 650, 'invoices': 1})], [({'trips': [[34, 410, 'plate'], [42, 410, 'tag'], [69, 525, 'plate'], [4, 525, 'tag'], [11, 250, 'exempt'], [87, 525, 'tag']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 10, 'invoice_fee': 400, 'cycle_days': 30}, {'tag': 1315, 'plate': 2063, 'invoices': 2}), ({'trips': [[77, 250, 'plate'], [50, 175, 'plate'], [14, 175, 'tag'], [81, 250, 'plate'], [89, 333, 'tag'], [61, 250, 'tag'], [19, 333, 'tag'], [9, 333, 'tag']], 'plate_surcharge_pct': 25, 'tag_discount_pct': 5, 'invoice_fee': 150, 'cycle_days': 31}, {'tag': 1356, 'plate': 1145, 'invoices': 2}), ({'trips': [[33, 333, 'plate']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 10, 'invoice_fee': 200, 'cycle_days': 31}, {'tag': 0, 'plate': 650, 'invoices': 1}), ({'trips': [[76, 250, 'tag'], [39, 175, 'plate'], [95, 175, 'plate'], [20, 333, 'plate'], [78, 410, 'exempt'], [59, 250, 'plate'], [88, 410, 'tag'], [5, 175, 'plate']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 5, 'invoice_fee': 150, 'cycle_days': 31}, {'tag': 628, 'plate': 1949, 'invoices': 3}), ({'trips': [[55, 410, 'exempt']], 'plate_surcharge_pct': 25, 'tag_discount_pct': 5, 'invoice_fee': 200, 'cycle_days': 31}, {'tag': 0, 'plate': 0, 'invoices': 0}), ({'trips': [[3, 410, 'exempt'], [4, 410, 'tag']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 10, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 369, 'plate': 0, 'invoices': 0}), ({'trips': [[19, 525, 'plate'], [51, 410, 'plate']], 'plate_surcharge_pct': 25, 'tag_discount_pct': 15, 'invoice_fee': 400, 'cycle_days': 31}, {'tag': 0, 'plate': 1970, 'invoices': 2}), ({'trips': [[29, 250, 'plate'], [30, 250, 'plate'], [5, 333, 'tag']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 15, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 284, 'plate': 1076, 'invoices': 2})], [({'trips': [[40, 410, 'tag'], [72, 250, 'exempt'], [22, 410, 'tag'], [1, 525, 'exempt'], [12, 410, 'plate'], [67, 525, 'plate'], [31, 410, 'tag']], 'plate_surcharge_pct': 25, 'tag_discount_pct': 5, 'invoice_fee': 150, 'cycle_days': 31}, {'tag': 1170, 'plate': 1470, 'invoices': 2}), ({'trips': [[3, 410, 'exempt'], [4, 410, 'tag']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 10, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 369, 'plate': 0, 'invoices': 0}), ({'trips': [[29, 250, 'plate'], [30, 250, 'plate'], [5, 333, 'tag']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 15, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 284, 'plate': 1076, 'invoices': 2}), ({'trips': [[52, 175, 'plate'], [89, 525, 'tag'], [15, 333, 'plate'], [70, 333, 'plate'], [65, 333, 'tag'], [45, 250, 'tag'], [80, 175, 'tag'], [82, 410, 'tag']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 10, 'invoice_fee': 150, 'cycle_days': 31}, {'tag': 1525, 'plate': 1713, 'invoices': 3}), ({'trips': [[12, 250, 'exempt'], [79, 175, 'plate'], [39, 175, 'plate'], [33, 175, 'plate'], [59, 525, 'tag']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 15, 'invoice_fee': 400, 'cycle_days': 31}, {'tag': 447, 'plate': 1589, 'invoices': 2}), ({'trips': [[69, 525, 'tag'], [7, 525, 'plate'], [83, 410, 'plate'], [84, 333, 'tag'], [1, 175, 'plate'], [52, 175, 'plate'], [0, 525, 'plate'], [33, 410, 'plate']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 10, 'invoice_fee': 150, 'cycle_days': 30}, {'tag': 773, 'plate': 3782, 'invoices': 3}), ({'trips': [[1, 525, 'plate'], [80, 333, 'tag'], [16, 250, 'tag'], [26, 525, 'plate'], [81, 410, 'tag'], [16, 525, 'plate'], [22, 250, 'plate']], 'plate_surcharge_pct': 25, 'tag_discount_pct': 5, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 945, 'plate': 2484, 'invoices': 1}), ({'trips': [[59, 410, 'plate']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 15, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 0, 'plate': 815, 'invoices': 1})], [({'trips': [[29, 250, 'plate'], [30, 250, 'plate'], [5, 333, 'tag']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 15, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 284, 'plate': 1076, 'invoices': 2}), ({'trips': [[64, 410, 'tag'], [37, 250, 'plate'], [70, 410, 'exempt'], [69, 333, 'plate'], [15, 250, 'tag']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 5, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 628, 'plate': 1188, 'invoices': 2}), ({'trips': [[39, 175, 'exempt'], [88, 250, 'exempt'], [26, 333, 'plate'], [38, 250, 'plate'], [87, 333, 'plate'], [91, 333, 'tag'], [95, 333, 'plate'], [21, 333, 'exempt']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 15, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 284, 'plate': 2675, 'invoices': 4}), ({'trips': [[89, 410, 'tag'], [63, 250, 'plate'], [89, 333, 'plate']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 10, 'invoice_fee': 150, 'cycle_days': 31}, {'tag': 369, 'plate': 1025, 'invoices': 1}), ({'trips': [[3, 410, 'exempt'], [4, 410, 'tag']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 10, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 369, 'plate': 0, 'invoices': 0}), ({'trips': [[45, 175, 'plate']], 'plate_surcharge_pct': 25, 'tag_discount_pct': 5, 'invoice_fee': 400, 'cycle_days': 31}, {'tag': 0, 'plate': 619, 'invoices': 1}), ({'trips': [[21, 333, 'tag'], [53, 175, 'tag']], 'plate_surcharge_pct': 25, 'tag_discount_pct': 10, 'invoice_fee': 400, 'cycle_days': 31}, {'tag': 458, 'plate': 0, 'invoices': 0}), ({'trips': [[16, 410, 'tag'], [38, 333, 'plate'], [40, 175, 'plate'], [91, 250, 'exempt'], [67, 250, 'tag']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 5, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 628, 'plate': 963, 'invoices': 1})], [({'trips': [[34, 175, 'plate'], [12, 175, 'plate'], [40, 250, 'plate'], [83, 525, 'tag'], [79, 250, 'plate']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 10, 'invoice_fee': 150, 'cycle_days': 30}, {'tag': 473, 'plate': 1726, 'invoices': 3}), ({'trips': [[23, 175, 'plate'], [66, 525, 'plate'], [52, 410, 'plate'], [73, 175, 'plate'], [39, 410, 'exempt'], [44, 250, 'tag'], [20, 333, 'tag'], [66, 410, 'exempt']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 5, 'invoice_fee': 400, 'cycle_days': 30}, {'tag': 555, 'plate': 3129, 'invoices': 3}), ({'trips': [[83, 175, 'exempt'], [80, 333, 'plate']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 10, 'invoice_fee': 400, 'cycle_days': 31}, {'tag': 0, 'plate': 900, 'invoices': 1}), ({'trips': [[3, 410, 'exempt'], [4, 410, 'tag']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 10, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 369, 'plate': 0, 'invoices': 0}), ({'trips': [[29, 250, 'plate'], [30, 250, 'plate'], [5, 333, 'tag']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 15, 'invoice_fee': 200, 'cycle_days': 30}, {'tag': 284, 'plate': 1076, 'invoices': 2}), ({'trips': [[67, 525, 'tag'], [87, 525, 'exempt'], [47, 525, 'tag'], [12, 250, 'tag'], [26, 250, 'exempt']], 'plate_surcharge_pct': 35, 'tag_discount_pct': 5, 'invoice_fee': 400, 'cycle_days': 30}, {'tag': 1236, 'plate': 0, 'invoices': 0}), ({'trips': [[88, 175, 'tag']], 'plate_surcharge_pct': 25, 'tag_discount_pct': 5, 'invoice_fee': 400, 'cycle_days': 30}, {'tag': 167, 'plate': 0, 'invoices': 0}), ({'trips': [[92, 525, 'tag'], [74, 333, 'tag'], [73, 333, 'plate']], 'plate_surcharge_pct': 50, 'tag_discount_pct': 10, 'invoice_fee': 200, 'cycle_days': 31}, {'tag': 773, 'plate': 700, 'invoices': 1})]]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check('fee oracle' + ' %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
fee oracle 0{'invoices': 0, 'plate': 0, 'tag': 447}{'invoices': 0, 'plate': 0, 'tag': 447}Passed
fee oracle 1{'invoices': 1, 'plate': 200, 'tag': 369}{'invoices': 0, 'plate': 0, 'tag': 369}Failed
fee oracle 2{'invoices': 1, 'plate': 600, 'tag': 1300}{'invoices': 1, 'plate': 600, 'tag': 1300}Passed
fee oracle 3{'invoices': 2, 'plate': 976, 'tag': 149}{'invoices': 2, 'plate': 976, 'tag': 149}Passed
fee oracle 4{'invoices': 1, 'plate': 200, 'tag': 284}{'invoices': 0, 'plate': 0, 'tag': 284}Failed
fee oracle 5{'invoices': 2, 'plate': 1076, 'tag': 284}{'invoices': 2, 'plate': 1076, 'tag': 284}Passed
fee oracle 6{'invoices': 3, 'plate': 2940, 'tag': 0}{'invoices': 3, 'plate': 2940, 'tag': 0}Passed
fee oracle 7{'invoices': 2, 'plate': 850, 'tag': 369}{'invoices': 1, 'plate': 650, 'tag': 369}Failed

SHA-256 / be0aee9dcc1a0358af1cb6e805edd0f0b53c04ad0240cfac66e40e45b4fd45ec

HELD IN THE MEMBER ARCHIVE

The verified repair and its recorded checks are member-only.

This mechanism has 8 recorded checks per implementation. The open-access tier publishes the failure and the unsuccessful fix; the repaired source that passes every check, and the observations that prove it, are available to members.

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Verification & scope

A deterministic, bounded toy model with a stipulated contract; it makes no claim of conformance to any agency manual or 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.

Observations recorded using Python 3.12.14 at 2026-09-29T14:48:03.827450+00:00.

Case digest / 088283756421ad590e70aad58b6ddd176869852c4d2bf363f9a75759b9f20d21