FA-85641 / Ride-hailing fare and surge pricing / Open access

Airport dropoff charged the pickup fee · case 01

Trips to the airport are charged the higher pickup fee.

Verified by executionVariant 1 · 7 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The dropoff side reads the pickup fee entry.

VERIFIED REPAIR

Charge the pickup fee for pickups and the dropoff fee for dropoffs.

Unsuccessful approach: Omitting the dropoff fee entirely under-charges airport dropoffs.

Case contract

Zone names are case-insensitive (normalized upper case). A flat fare table keyed "A|B" applies in both directions; a flat fare (0 is a valid promotional flat) is never surged. Otherwise the metered fare is surged (tenths, half up). Airport fees apply separately: the pickup fee of the pickup zone and the dropoff fee of the dropoff zone. Tolls are added last. Return [fare, flat|metered].

Why this case matters

Ride-hailing prices are computed per trip at scale; ordering, unit and boundary slips become systematic over- or under-charging.

1 / The failure

Exit 1

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

N = 1
observations = []
def solve(table, pickup_zone, drop_zone, metered, tolls, surge, airport_fees):
    p, d = pickup_zone.upper(), drop_zone.upper()
    flat = table.get(p + '|' + d, table.get(d + '|' + p))
    if flat is not None:
        fare, kind = flat, 'flat'
    else:
        fare, kind = (metered * surge * 2 + 10) // 20, 'metered'
    fare += airport_fees.get(p, {}).get('pickup', 0) + airport_fees.get(d, {}).get('pickup', 0)
    return [fare + tolls, kind]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('regression: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'DT', 'AIR', 4387, 250, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5050, 'flat']),
  ('partial repair probe: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'DT', 'AIR', 2756, 0, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4800, 'flat']),
  ('second regression',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'DT', 'air', 5529, 600, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5400, 'flat']),
  ('normal control 1',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'AIR', 'MID', 1177, 0, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [2854, 'metered']),
  ('normal control 2',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'Dt', 'DT', 3757, 0, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5636, 'metered']),
  ('normal control 3',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'AIR', 'MID', 3578, 250, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4328, 'metered']),
  ('normal control 4',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'MID', 'DT', 4097, 250, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [6396, 'metered'])],
 [('regression: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'UNI', 'air', 3297, 250, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4450, 'flat']),
  ('partial repair probe: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'Dt', 'AIR', 991, 0, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4800, 'flat']),
  ('second regression',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'DT', 'air', 4614, 600, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5400, 'flat']),
  ('normal control 1',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'SHUT', 'UNI', 2643, 0, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [2643, 'metered']),
  ('normal control 2',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'air', 'Dt', 2569, 0, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5000, 'flat']),
  ('normal control 3',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'SHUT', 'DT', 5450, 0, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [0, 'flat']),
  ('normal control 4',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'AIR', 'SHUT', 4706, 600, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [10512, 'metered'])],
 [('regression: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'MID', 'air', 3585, 600, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [8070, 'metered']),
  ('partial repair probe: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'UNI', 'AIR', 4123, 600, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4800, 'flat']),
  ('second regression',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'UNI', 'AIR', 4026, 600, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4800, 'flat']),
  ('normal control 1',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'Dt', 'DT', 4305, 250, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [8860, 'metered']),
  ('normal control 2',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'MID', 'MID', 2606, 0, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5212, 'metered']),
  ('normal control 3',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'air', 'Dt', 4867, 250, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5250, 'flat']),
  ('normal control 4',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'air', 'SHUT', 4760, 250, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5510, 'metered'])],
 [('regression: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'SHUT', 'air', 4285, 600, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5185, 'metered']),
  ('partial repair probe: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'DT', 'AIR', 5437, 250, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5050, 'flat']),
  ('second regression',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'UNI', 'AIR', 1363, 250, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4450, 'flat']),
  ('normal control 1',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'Dt', 'DT', 4478, 600, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [7317, 'metered']),
  ('normal control 2',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'air', 'UNI', 5924, 600, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5000, 'flat']),
  ('normal control 3',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'air', 'DT', 1853, 250, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5250, 'flat']),
  ('normal control 4',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'Dt', 'MID', 4781, 0, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [7172, 'metered'])],
 [('regression: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'DT', 'air', 1974, 250, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5050, 'flat']),
  ('partial repair probe: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'MID', 'AIR', 1558, 0, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [2637, 'metered']),
  ('second regression',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'air', 'AIR', 2287, 600, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4831, 'metered']),
  ('normal control 1',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'AIR', 'Dt', 2942, 250, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5250, 'flat']),
  ('normal control 2',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'AIR', 'SHUT', 3509, 0, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4009, 'metered']),
  ('normal control 3',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'MID', 'SHUT', 2704, 0, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [2704, 'metered']),
  ('normal control 4',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'SHUT', 'DT', 2888, 0, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [0, 'flat'])]]
for label, args, expected in fixtures[N-1]:
    check(label, 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 fixture	Actual	Expected	Outcome
regression: airport fee sides	`[5250, 'flat']`	`[5050, 'flat']`	Failed
partial repair probe: airport fee sides	`[5000, 'flat']`	`[4800, 'flat']`	Failed
second regression	`[5600, 'flat']`	`[5400, 'flat']`	Failed
normal control 1	`[2854, 'metered']`	`[2854, 'metered']`	Passed
normal control 2	`[5636, 'metered']`	`[5636, 'metered']`	Passed
normal control 3	`[4328, 'metered']`	`[4328, 'metered']`	Passed
normal control 4	`[6396, 'metered']`	`[6396, 'metered']`	Passed

SHA-256 / 01d5f1506ac4ee5deee3b44cebf2ede2d5992646b2093ada215c0b803ca551b2

2 / The unsuccessful fix

Exit 1

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

N = 1
observations = []
def solve(table, pickup_zone, drop_zone, metered, tolls, surge, airport_fees):
    p, d = pickup_zone.upper(), drop_zone.upper()
    flat = table.get(p + '|' + d, table.get(d + '|' + p))
    if flat is not None:
        fare, kind = flat, 'flat'
    else:
        fare, kind = (metered * surge * 2 + 10) // 20, 'metered'
    fare += airport_fees.get(p, {}).get('pickup', 0)
    return [fare + tolls, kind]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('regression: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'DT', 'AIR', 4387, 250, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5050, 'flat']),
  ('partial repair probe: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'DT', 'AIR', 2756, 0, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4800, 'flat']),
  ('second regression',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'DT', 'air', 5529, 600, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5400, 'flat']),
  ('normal control 1',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'AIR', 'MID', 1177, 0, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [2854, 'metered']),
  ('normal control 2',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'Dt', 'DT', 3757, 0, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5636, 'metered']),
  ('normal control 3',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'AIR', 'MID', 3578, 250, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4328, 'metered']),
  ('normal control 4',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'MID', 'DT', 4097, 250, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [6396, 'metered'])],
 [('regression: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'UNI', 'air', 3297, 250, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4450, 'flat']),
  ('partial repair probe: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'Dt', 'AIR', 991, 0, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4800, 'flat']),
  ('second regression',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'DT', 'air', 4614, 600, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5400, 'flat']),
  ('normal control 1',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'SHUT', 'UNI', 2643, 0, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [2643, 'metered']),
  ('normal control 2',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'air', 'Dt', 2569, 0, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5000, 'flat']),
  ('normal control 3',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'SHUT', 'DT', 5450, 0, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [0, 'flat']),
  ('normal control 4',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'AIR', 'SHUT', 4706, 600, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [10512, 'metered'])],
 [('regression: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'MID', 'air', 3585, 600, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [8070, 'metered']),
  ('partial repair probe: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'UNI', 'AIR', 4123, 600, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4800, 'flat']),
  ('second regression',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'UNI', 'AIR', 4026, 600, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4800, 'flat']),
  ('normal control 1',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'Dt', 'DT', 4305, 250, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [8860, 'metered']),
  ('normal control 2',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'MID', 'MID', 2606, 0, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5212, 'metered']),
  ('normal control 3',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'air', 'Dt', 4867, 250, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5250, 'flat']),
  ('normal control 4',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'air', 'SHUT', 4760, 250, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5510, 'metered'])],
 [('regression: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'SHUT', 'air', 4285, 600, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5185, 'metered']),
  ('partial repair probe: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'DT', 'AIR', 5437, 250, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5050, 'flat']),
  ('second regression',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'UNI', 'AIR', 1363, 250, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4450, 'flat']),
  ('normal control 1',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'Dt', 'DT', 4478, 600, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [7317, 'metered']),
  ('normal control 2',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'air', 'UNI', 5924, 600, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5000, 'flat']),
  ('normal control 3',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'air', 'DT', 1853, 250, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5250, 'flat']),
  ('normal control 4',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'Dt', 'MID', 4781, 0, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [7172, 'metered'])],
 [('regression: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'DT', 'air', 1974, 250, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5050, 'flat']),
  ('partial repair probe: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'MID', 'AIR', 1558, 0, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [2637, 'metered']),
  ('second regression',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'air', 'AIR', 2287, 600, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4831, 'metered']),
  ('normal control 1',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'AIR', 'Dt', 2942, 250, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5250, 'flat']),
  ('normal control 2',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'AIR', 'SHUT', 3509, 0, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4009, 'metered']),
  ('normal control 3',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'MID', 'SHUT', 2704, 0, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [2704, 'metered']),
  ('normal control 4',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'SHUT', 'DT', 2888, 0, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [0, 'flat'])]]
for label, args, expected in fixtures[N-1]:
    check(label, 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 fixture	Actual	Expected	Outcome
regression: airport fee sides	`[4750, 'flat']`	`[5050, 'flat']`	Failed
partial repair probe: airport fee sides	`[4500, 'flat']`	`[4800, 'flat']`	Failed
second regression	`[5100, 'flat']`	`[5400, 'flat']`	Failed
normal control 1	`[2854, 'metered']`	`[2854, 'metered']`	Passed
normal control 2	`[5636, 'metered']`	`[5636, 'metered']`	Passed
normal control 3	`[4328, 'metered']`	`[4328, 'metered']`	Passed
normal control 4	`[6396, 'metered']`	`[6396, 'metered']`	Passed

SHA-256 / fb4465e0a527f44940fdcf66286aa7ffb5e64a619f73a3de1eea21a42c9e8d1c

3 / The verified repair

Exit 0

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

N = 1
observations = []
def solve(table, pickup_zone, drop_zone, metered, tolls, surge, airport_fees):
    p, d = pickup_zone.upper(), drop_zone.upper()
    flat = table.get(p + '|' + d, table.get(d + '|' + p))
    if flat is not None:
        fare, kind = flat, 'flat'
    else:
        fare, kind = (metered * surge * 2 + 10) // 20, 'metered'
    fare += airport_fees.get(p, {}).get('pickup', 0) + airport_fees.get(d, {}).get('dropoff', 0)
    return [fare + tolls, kind]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('regression: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'DT', 'AIR', 4387, 250, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5050, 'flat']),
  ('partial repair probe: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'DT', 'AIR', 2756, 0, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4800, 'flat']),
  ('second regression',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'DT', 'air', 5529, 600, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5400, 'flat']),
  ('normal control 1',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'AIR', 'MID', 1177, 0, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [2854, 'metered']),
  ('normal control 2',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'Dt', 'DT', 3757, 0, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5636, 'metered']),
  ('normal control 3',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'AIR', 'MID', 3578, 250, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4328, 'metered']),
  ('normal control 4',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'MID', 'DT', 4097, 250, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [6396, 'metered'])],
 [('regression: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'UNI', 'air', 3297, 250, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4450, 'flat']),
  ('partial repair probe: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'Dt', 'AIR', 991, 0, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4800, 'flat']),
  ('second regression',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'DT', 'air', 4614, 600, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5400, 'flat']),
  ('normal control 1',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'SHUT', 'UNI', 2643, 0, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [2643, 'metered']),
  ('normal control 2',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'air', 'Dt', 2569, 0, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5000, 'flat']),
  ('normal control 3',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'SHUT', 'DT', 5450, 0, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [0, 'flat']),
  ('normal control 4',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'AIR', 'SHUT', 4706, 600, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [10512, 'metered'])],
 [('regression: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'MID', 'air', 3585, 600, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [8070, 'metered']),
  ('partial repair probe: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'UNI', 'AIR', 4123, 600, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4800, 'flat']),
  ('second regression',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'UNI', 'AIR', 4026, 600, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4800, 'flat']),
  ('normal control 1',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'Dt', 'DT', 4305, 250, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [8860, 'metered']),
  ('normal control 2',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'MID', 'MID', 2606, 0, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5212, 'metered']),
  ('normal control 3',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'air', 'Dt', 4867, 250, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5250, 'flat']),
  ('normal control 4',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'air', 'SHUT', 4760, 250, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5510, 'metered'])],
 [('regression: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'SHUT', 'air', 4285, 600, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5185, 'metered']),
  ('partial repair probe: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'DT', 'AIR', 5437, 250, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5050, 'flat']),
  ('second regression',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'UNI', 'AIR', 1363, 250, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4450, 'flat']),
  ('normal control 1',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'Dt', 'DT', 4478, 600, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [7317, 'metered']),
  ('normal control 2',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'air', 'UNI', 5924, 600, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5000, 'flat']),
  ('normal control 3',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'air', 'DT', 1853, 250, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5250, 'flat']),
  ('normal control 4',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'Dt', 'MID', 4781, 0, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [7172, 'metered'])],
 [('regression: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'DT', 'air', 1974, 250, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5050, 'flat']),
  ('partial repair probe: airport fee sides',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'MID', 'AIR', 1558, 0, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [2637, 'metered']),
  ('second regression',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'air', 'AIR', 2287, 600, 15,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4831, 'metered']),
  ('normal control 1',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'AIR', 'Dt', 2942, 250, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [5250, 'flat']),
  ('normal control 2',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'AIR', 'SHUT', 3509, 0, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [4009, 'metered']),
  ('normal control 3',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'MID', 'SHUT', 2704, 0, 10,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [2704, 'metered']),
  ('normal control 4',
   [{'AIR|DT': 4500, 'AIR|UNI': 3900, 'DT|SHUT': 0}, 'SHUT', 'DT', 2888, 0, 20,
    {'AIR': {'dropoff': 300, 'pickup': 500}}],
   [0, 'flat'])]]
for label, args, expected in fixtures[N-1]:
    check(label, 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 fixture	Actual	Expected	Outcome
regression: airport fee sides	`[5050, 'flat']`	`[5050, 'flat']`	Passed
partial repair probe: airport fee sides	`[4800, 'flat']`	`[4800, 'flat']`	Passed
second regression	`[5400, 'flat']`	`[5400, 'flat']`	Passed
normal control 1	`[2854, 'metered']`	`[2854, 'metered']`	Passed
normal control 2	`[5636, 'metered']`	`[5636, 'metered']`	Passed
normal control 3	`[4328, 'metered']`	`[4328, 'metered']`	Passed
normal control 4	`[6396, 'metered']`	`[6396, 'metered']`	Passed

SHA-256 / 99e3bd0312adb52e0afdaf9a8f9ac348b2d4cdde33bc7ef40f8ca4dee7ecc3f6

Verification & scope

A deterministic toy pricing contract stipulated for this example; it does not reproduce the pricing of any real ride-hailing operator or regulator. 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 2026-09-29T14:50:42.263367+00:00.

Case digest / d3ffc1c88c9499663d923a3b9bd548f7a94c35240a57ba99a953da0d932480db