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FA-85341 / Ride-hailing fare and surge pricing / Open access

Booking fee absorbed into the minimum fare · case 01

Short trips charged exactly the minimum fare, missing the booking fee.

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

ROOT CAUSE

The minimum is compared after adding the booking fee, so the fee disappears into the minimum.

VERIFIED REPAIR

Apply the minimum to the metered subtotal, then add the booking fee.

Unsuccessful approach: Dropping the fee whenever the minimum applies still omits it on the short trips it was meant for.

Case contract

All money is integer cents. Distance charge = meters x per_km / 1000 and time charge = seconds x per_min / 60, each rounded half up to a cent on its own. Subtotal = base + distance + time. The minimum fare applies to that subtotal only; the booking fee is added after the minimum. Return the distance charge, time charge and fare.

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(trip, rate):
    def half_up(num, den):
        return (num * 2 + den) // (den * 2)
    dist = half_up(trip['meters'] * rate['per_km'], 1000)
    tm = half_up(trip['seconds'] * rate['per_min'], 60)
    sub = rate['base'] + dist + tm
    fare = max(sub + rate['booking_fee'], rate['minimum'])
    return {'distance': dist, 'time': tm, 'fare': fare}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('regression: minimum before booking fee',
   [{'meters': 0, 'seconds': 30},
    {'base': 250, 'booking_fee': 250, 'minimum': 1000, 'per_km': 125, 'per_min': 35}],
   {'distance': 0, 'fare': 1250, 'time': 18}),
  ('partial repair probe: minimum before booking fee',
   [{'meters': 4, 'seconds': 30},
    {'base': 150, 'booking_fee': 250, 'minimum': 500, 'per_km': 95, 'per_min': 30}],
   {'distance': 0, 'fare': 750, 'time': 15}),
  ('second regression',
   [{'meters': 0, 'seconds': 30},
    {'base': 0, 'booking_fee': 175, 'minimum': 700, 'per_km': 110, 'per_min': 30}],
   {'distance': 0, 'fare': 875, 'time': 15}),
  ('normal control 1',
   [{'meters': 2500, 'seconds': 30},
    {'base': 250, 'booking_fee': 0, 'minimum': 1000, 'per_km': 125, 'per_min': 15}],
   {'distance': 313, 'fare': 1000, 'time': 8}),
  ('normal control 2',
   [{'meters': 0, 'seconds': 61},
    {'base': 0, 'booking_fee': 0, 'minimum': 700, 'per_km': 125, 'per_min': 15}],
   {'distance': 0, 'fare': 700, 'time': 15}),
  ('normal control 3',
   [{'meters': 500, 'seconds': 0},
    {'base': 0, 'booking_fee': 0, 'minimum': 500, 'per_km': 250, 'per_min': 30}],
   {'distance': 125, 'fare': 500, 'time': 0}),
  ('normal control 4',
   [{'meters': 0, 'seconds': 61},
    {'base': 250, 'booking_fee': 0, 'minimum': 500, 'per_km': 110, 'per_min': 35}],
   {'distance': 0, 'fare': 500, 'time': 36})],
 [('regression: minimum before booking fee',
   [{'meters': 2500, 'seconds': 90},
    {'base': 0, 'booking_fee': 250, 'minimum': 700, 'per_km': 125, 'per_min': 15}],
   {'distance': 313, 'fare': 950, 'time': 23}),
  ('partial repair probe: minimum before booking fee',
   [{'meters': 0, 'seconds': 0},
    {'base': 250, 'booking_fee': 175, 'minimum': 1000, 'per_km': 95, 'per_min': 35}],
   {'distance': 0, 'fare': 1175, 'time': 0}),
  ('second regression',
   [{'meters': 0, 'seconds': 90},
    {'base': 250, 'booking_fee': 175, 'minimum': 1000, 'per_km': 110, 'per_min': 30}],
   {'distance': 0, 'fare': 1175, 'time': 45}),
  ('normal control 1',
   [{'meters': 15327, 'seconds': 30},
    {'base': 0, 'booking_fee': 250, 'minimum': 700, 'per_km': 125, 'per_min': 30}],
   {'distance': 1916, 'fare': 2181, 'time': 15}),
  ('normal control 2',
   [{'meters': 500, 'seconds': 1882},
    {'base': 0, 'booking_fee': 0, 'minimum': 500, 'per_km': 250, 'per_min': 25}],
   {'distance': 125, 'fare': 909, 'time': 784}),
  ('normal control 3',
   [{'meters': 500, 'seconds': 61},
    {'base': 250, 'booking_fee': 0, 'minimum': 700, 'per_km': 95, 'per_min': 30}],
   {'distance': 48, 'fare': 700, 'time': 31}),
  ('normal control 4',
   [{'meters': 500, 'seconds': 0},
    {'base': 250, 'booking_fee': 0, 'minimum': 700, 'per_km': 95, 'per_min': 35}],
   {'distance': 48, 'fare': 700, 'time': 0})],
 [('regression: minimum before booking fee',
   [{'meters': 1004, 'seconds': 0},
    {'base': 0, 'booking_fee': 175, 'minimum': 500, 'per_km': 250, 'per_min': 15}],
   {'distance': 251, 'fare': 675, 'time': 0}),
  ('partial repair probe: minimum before booking fee',
   [{'meters': 4, 'seconds': 0},
    {'base': 150, 'booking_fee': 250, 'minimum': 700, 'per_km': 110, 'per_min': 30}],
   {'distance': 0, 'fare': 950, 'time': 0}),
  ('second regression',
   [{'meters': 12, 'seconds': 90},
    {'base': 250, 'booking_fee': 250, 'minimum': 700, 'per_km': 110, 'per_min': 30}],
   {'distance': 1, 'fare': 950, 'time': 45}),
  ('normal control 1',
   [{'meters': 0, 'seconds': 61},
    {'base': 250, 'booking_fee': 0, 'minimum': 500, 'per_km': 110, 'per_min': 15}],
   {'distance': 0, 'fare': 500, 'time': 15}),
  ('normal control 2',
   [{'meters': 6354, 'seconds': 30},
    {'base': 0, 'booking_fee': 0, 'minimum': 500, 'per_km': 110, 'per_min': 35}],
   {'distance': 699, 'fare': 717, 'time': 18}),
  ('normal control 3',
   [{'meters': 4, 'seconds': 61},
    {'base': 250, 'booking_fee': 0, 'minimum': 500, 'per_km': 95, 'per_min': 35}],
   {'distance': 0, 'fare': 500, 'time': 36}),
  ('normal control 4',
   [{'meters': 23665, 'seconds': 30},
    {'base': 0, 'booking_fee': 175, 'minimum': 500, 'per_km': 110, 'per_min': 15}],
   {'distance': 2603, 'fare': 2786, 'time': 8})],
 [('regression: minimum before booking fee',
   [{'meters': 500, 'seconds': 30},
    {'base': 150, 'booking_fee': 175, 'minimum': 1000, 'per_km': 110, 'per_min': 15}],
   {'distance': 55, 'fare': 1175, 'time': 8}),
  ('partial repair probe: minimum before booking fee',
   [{'meters': 0, 'seconds': 1374},
    {'base': 0, 'booking_fee': 175, 'minimum': 700, 'per_km': 110, 'per_min': 15}],
   {'distance': 0, 'fare': 875, 'time': 344}),
  ('second regression',
   [{'meters': 500, 'seconds': 30},
    {'base': 0, 'booking_fee': 175, 'minimum': 500, 'per_km': 110, 'per_min': 35}],
   {'distance': 55, 'fare': 675, 'time': 18}),
  ('normal control 1',
   [{'meters': 1004, 'seconds': 61},
    {'base': 0, 'booking_fee': 0, 'minimum': 500, 'per_km': 95, 'per_min': 15}],
   {'distance': 95, 'fare': 500, 'time': 15}),
  ('normal control 2',
   [{'meters': 0, 'seconds': 30},
    {'base': 150, 'booking_fee': 0, 'minimum': 1000, 'per_km': 125, 'per_min': 30}],
   {'distance': 0, 'fare': 1000, 'time': 15}),
  ('normal control 3',
   [{'meters': 12, 'seconds': 61},
    {'base': 150, 'booking_fee': 0, 'minimum': 500, 'per_km': 110, 'per_min': 15}],
   {'distance': 1, 'fare': 500, 'time': 15}),
  ('normal control 4',
   [{'meters': 24766, 'seconds': 30},
    {'base': 250, 'booking_fee': 250, 'minimum': 1000, 'per_km': 250, 'per_min': 30}],
   {'distance': 6192, 'fare': 6707, 'time': 15})],
 [('regression: minimum before booking fee',
   [{'meters': 500, 'seconds': 61},
    {'base': 150, 'booking_fee': 250, 'minimum': 500, 'per_km': 125, 'per_min': 35}],
   {'distance': 63, 'fare': 750, 'time': 36}),
  ('partial repair probe: minimum before booking fee',
   [{'meters': 500, 'seconds': 90},
    {'base': 0, 'booking_fee': 250, 'minimum': 700, 'per_km': 110, 'per_min': 35}],
   {'distance': 55, 'fare': 950, 'time': 53}),
  ('second regression',
   [{'meters': 2500, 'seconds': 30},
    {'base': 0, 'booking_fee': 175, 'minimum': 700, 'per_km': 250, 'per_min': 15}],
   {'distance': 625, 'fare': 875, 'time': 8}),
  ('normal control 1',
   [{'meters': 4, 'seconds': 2383},
    {'base': 250, 'booking_fee': 0, 'minimum': 700, 'per_km': 250, 'per_min': 35}],
   {'distance': 1, 'fare': 1641, 'time': 1390}),
  ('normal control 2',
   [{'meters': 0, 'seconds': 1117},
    {'base': 250, 'booking_fee': 250, 'minimum': 700, 'per_km': 125, 'per_min': 30}],
   {'distance': 0, 'fare': 1059, 'time': 559}),
  ('normal control 3',
   [{'meters': 0, 'seconds': 30}, {'base': 0, 'booking_fee': 0, 'minimum': 700, 'per_km': 95, 'per_min': 35}],
   {'distance': 0, 'fare': 700, 'time': 18}),
  ('normal control 4',
   [{'meters': 12, 'seconds': 30},
    {'base': 150, 'booking_fee': 0, 'minimum': 500, 'per_km': 110, 'per_min': 15}],
   {'distance': 1, 'fare': 500, 'time': 8})]]
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 fixtureActualExpectedOutcome
regression: minimum before booking fee{'distance': 0, 'fare': 1000, 'time': 18}{'distance': 0, 'fare': 1250, 'time': 18}Failed
partial repair probe: minimum before booking fee{'distance': 0, 'fare': 500, 'time': 15}{'distance': 0, 'fare': 750, 'time': 15}Failed
second regression{'distance': 0, 'fare': 700, 'time': 15}{'distance': 0, 'fare': 875, 'time': 15}Failed
normal control 1{'distance': 313, 'fare': 1000, 'time': 8}{'distance': 313, 'fare': 1000, 'time': 8}Passed
normal control 2{'distance': 0, 'fare': 700, 'time': 15}{'distance': 0, 'fare': 700, 'time': 15}Passed
normal control 3{'distance': 125, 'fare': 500, 'time': 0}{'distance': 125, 'fare': 500, 'time': 0}Passed
normal control 4{'distance': 0, 'fare': 500, 'time': 36}{'distance': 0, 'fare': 500, 'time': 36}Passed

SHA-256 / 657791282608213df8531d4837d43bc378231655b5c44a94d58a301553289045

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(trip, rate):
    def half_up(num, den):
        return (num * 2 + den) // (den * 2)
    dist = half_up(trip['meters'] * rate['per_km'], 1000)
    tm = half_up(trip['seconds'] * rate['per_min'], 60)
    sub = rate['base'] + dist + tm
    fare = max(sub, rate['minimum']) + (rate['booking_fee'] if sub >= rate['minimum'] else 0)
    return {'distance': dist, 'time': tm, 'fare': fare}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('regression: minimum before booking fee',
   [{'meters': 0, 'seconds': 30},
    {'base': 250, 'booking_fee': 250, 'minimum': 1000, 'per_km': 125, 'per_min': 35}],
   {'distance': 0, 'fare': 1250, 'time': 18}),
  ('partial repair probe: minimum before booking fee',
   [{'meters': 4, 'seconds': 30},
    {'base': 150, 'booking_fee': 250, 'minimum': 500, 'per_km': 95, 'per_min': 30}],
   {'distance': 0, 'fare': 750, 'time': 15}),
  ('second regression',
   [{'meters': 0, 'seconds': 30},
    {'base': 0, 'booking_fee': 175, 'minimum': 700, 'per_km': 110, 'per_min': 30}],
   {'distance': 0, 'fare': 875, 'time': 15}),
  ('normal control 1',
   [{'meters': 2500, 'seconds': 30},
    {'base': 250, 'booking_fee': 0, 'minimum': 1000, 'per_km': 125, 'per_min': 15}],
   {'distance': 313, 'fare': 1000, 'time': 8}),
  ('normal control 2',
   [{'meters': 0, 'seconds': 61},
    {'base': 0, 'booking_fee': 0, 'minimum': 700, 'per_km': 125, 'per_min': 15}],
   {'distance': 0, 'fare': 700, 'time': 15}),
  ('normal control 3',
   [{'meters': 500, 'seconds': 0},
    {'base': 0, 'booking_fee': 0, 'minimum': 500, 'per_km': 250, 'per_min': 30}],
   {'distance': 125, 'fare': 500, 'time': 0}),
  ('normal control 4',
   [{'meters': 0, 'seconds': 61},
    {'base': 250, 'booking_fee': 0, 'minimum': 500, 'per_km': 110, 'per_min': 35}],
   {'distance': 0, 'fare': 500, 'time': 36})],
 [('regression: minimum before booking fee',
   [{'meters': 2500, 'seconds': 90},
    {'base': 0, 'booking_fee': 250, 'minimum': 700, 'per_km': 125, 'per_min': 15}],
   {'distance': 313, 'fare': 950, 'time': 23}),
  ('partial repair probe: minimum before booking fee',
   [{'meters': 0, 'seconds': 0},
    {'base': 250, 'booking_fee': 175, 'minimum': 1000, 'per_km': 95, 'per_min': 35}],
   {'distance': 0, 'fare': 1175, 'time': 0}),
  ('second regression',
   [{'meters': 0, 'seconds': 90},
    {'base': 250, 'booking_fee': 175, 'minimum': 1000, 'per_km': 110, 'per_min': 30}],
   {'distance': 0, 'fare': 1175, 'time': 45}),
  ('normal control 1',
   [{'meters': 15327, 'seconds': 30},
    {'base': 0, 'booking_fee': 250, 'minimum': 700, 'per_km': 125, 'per_min': 30}],
   {'distance': 1916, 'fare': 2181, 'time': 15}),
  ('normal control 2',
   [{'meters': 500, 'seconds': 1882},
    {'base': 0, 'booking_fee': 0, 'minimum': 500, 'per_km': 250, 'per_min': 25}],
   {'distance': 125, 'fare': 909, 'time': 784}),
  ('normal control 3',
   [{'meters': 500, 'seconds': 61},
    {'base': 250, 'booking_fee': 0, 'minimum': 700, 'per_km': 95, 'per_min': 30}],
   {'distance': 48, 'fare': 700, 'time': 31}),
  ('normal control 4',
   [{'meters': 500, 'seconds': 0},
    {'base': 250, 'booking_fee': 0, 'minimum': 700, 'per_km': 95, 'per_min': 35}],
   {'distance': 48, 'fare': 700, 'time': 0})],
 [('regression: minimum before booking fee',
   [{'meters': 1004, 'seconds': 0},
    {'base': 0, 'booking_fee': 175, 'minimum': 500, 'per_km': 250, 'per_min': 15}],
   {'distance': 251, 'fare': 675, 'time': 0}),
  ('partial repair probe: minimum before booking fee',
   [{'meters': 4, 'seconds': 0},
    {'base': 150, 'booking_fee': 250, 'minimum': 700, 'per_km': 110, 'per_min': 30}],
   {'distance': 0, 'fare': 950, 'time': 0}),
  ('second regression',
   [{'meters': 12, 'seconds': 90},
    {'base': 250, 'booking_fee': 250, 'minimum': 700, 'per_km': 110, 'per_min': 30}],
   {'distance': 1, 'fare': 950, 'time': 45}),
  ('normal control 1',
   [{'meters': 0, 'seconds': 61},
    {'base': 250, 'booking_fee': 0, 'minimum': 500, 'per_km': 110, 'per_min': 15}],
   {'distance': 0, 'fare': 500, 'time': 15}),
  ('normal control 2',
   [{'meters': 6354, 'seconds': 30},
    {'base': 0, 'booking_fee': 0, 'minimum': 500, 'per_km': 110, 'per_min': 35}],
   {'distance': 699, 'fare': 717, 'time': 18}),
  ('normal control 3',
   [{'meters': 4, 'seconds': 61},
    {'base': 250, 'booking_fee': 0, 'minimum': 500, 'per_km': 95, 'per_min': 35}],
   {'distance': 0, 'fare': 500, 'time': 36}),
  ('normal control 4',
   [{'meters': 23665, 'seconds': 30},
    {'base': 0, 'booking_fee': 175, 'minimum': 500, 'per_km': 110, 'per_min': 15}],
   {'distance': 2603, 'fare': 2786, 'time': 8})],
 [('regression: minimum before booking fee',
   [{'meters': 500, 'seconds': 30},
    {'base': 150, 'booking_fee': 175, 'minimum': 1000, 'per_km': 110, 'per_min': 15}],
   {'distance': 55, 'fare': 1175, 'time': 8}),
  ('partial repair probe: minimum before booking fee',
   [{'meters': 0, 'seconds': 1374},
    {'base': 0, 'booking_fee': 175, 'minimum': 700, 'per_km': 110, 'per_min': 15}],
   {'distance': 0, 'fare': 875, 'time': 344}),
  ('second regression',
   [{'meters': 500, 'seconds': 30},
    {'base': 0, 'booking_fee': 175, 'minimum': 500, 'per_km': 110, 'per_min': 35}],
   {'distance': 55, 'fare': 675, 'time': 18}),
  ('normal control 1',
   [{'meters': 1004, 'seconds': 61},
    {'base': 0, 'booking_fee': 0, 'minimum': 500, 'per_km': 95, 'per_min': 15}],
   {'distance': 95, 'fare': 500, 'time': 15}),
  ('normal control 2',
   [{'meters': 0, 'seconds': 30},
    {'base': 150, 'booking_fee': 0, 'minimum': 1000, 'per_km': 125, 'per_min': 30}],
   {'distance': 0, 'fare': 1000, 'time': 15}),
  ('normal control 3',
   [{'meters': 12, 'seconds': 61},
    {'base': 150, 'booking_fee': 0, 'minimum': 500, 'per_km': 110, 'per_min': 15}],
   {'distance': 1, 'fare': 500, 'time': 15}),
  ('normal control 4',
   [{'meters': 24766, 'seconds': 30},
    {'base': 250, 'booking_fee': 250, 'minimum': 1000, 'per_km': 250, 'per_min': 30}],
   {'distance': 6192, 'fare': 6707, 'time': 15})],
 [('regression: minimum before booking fee',
   [{'meters': 500, 'seconds': 61},
    {'base': 150, 'booking_fee': 250, 'minimum': 500, 'per_km': 125, 'per_min': 35}],
   {'distance': 63, 'fare': 750, 'time': 36}),
  ('partial repair probe: minimum before booking fee',
   [{'meters': 500, 'seconds': 90},
    {'base': 0, 'booking_fee': 250, 'minimum': 700, 'per_km': 110, 'per_min': 35}],
   {'distance': 55, 'fare': 950, 'time': 53}),
  ('second regression',
   [{'meters': 2500, 'seconds': 30},
    {'base': 0, 'booking_fee': 175, 'minimum': 700, 'per_km': 250, 'per_min': 15}],
   {'distance': 625, 'fare': 875, 'time': 8}),
  ('normal control 1',
   [{'meters': 4, 'seconds': 2383},
    {'base': 250, 'booking_fee': 0, 'minimum': 700, 'per_km': 250, 'per_min': 35}],
   {'distance': 1, 'fare': 1641, 'time': 1390}),
  ('normal control 2',
   [{'meters': 0, 'seconds': 1117},
    {'base': 250, 'booking_fee': 250, 'minimum': 700, 'per_km': 125, 'per_min': 30}],
   {'distance': 0, 'fare': 1059, 'time': 559}),
  ('normal control 3',
   [{'meters': 0, 'seconds': 30}, {'base': 0, 'booking_fee': 0, 'minimum': 700, 'per_km': 95, 'per_min': 35}],
   {'distance': 0, 'fare': 700, 'time': 18}),
  ('normal control 4',
   [{'meters': 12, 'seconds': 30},
    {'base': 150, 'booking_fee': 0, 'minimum': 500, 'per_km': 110, 'per_min': 15}],
   {'distance': 1, 'fare': 500, 'time': 8})]]
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 fixtureActualExpectedOutcome
regression: minimum before booking fee{'distance': 0, 'fare': 1000, 'time': 18}{'distance': 0, 'fare': 1250, 'time': 18}Failed
partial repair probe: minimum before booking fee{'distance': 0, 'fare': 500, 'time': 15}{'distance': 0, 'fare': 750, 'time': 15}Failed
second regression{'distance': 0, 'fare': 700, 'time': 15}{'distance': 0, 'fare': 875, 'time': 15}Failed
normal control 1{'distance': 313, 'fare': 1000, 'time': 8}{'distance': 313, 'fare': 1000, 'time': 8}Passed
normal control 2{'distance': 0, 'fare': 700, 'time': 15}{'distance': 0, 'fare': 700, 'time': 15}Passed
normal control 3{'distance': 125, 'fare': 500, 'time': 0}{'distance': 125, 'fare': 500, 'time': 0}Passed
normal control 4{'distance': 0, 'fare': 500, 'time': 36}{'distance': 0, 'fare': 500, 'time': 36}Passed

SHA-256 / bb8da4b96573f39d114270d36494014e1a3c2b0301e770f270d10a78bd6be3dc

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(trip, rate):
    def half_up(num, den):
        return (num * 2 + den) // (den * 2)
    dist = half_up(trip['meters'] * rate['per_km'], 1000)
    tm = half_up(trip['seconds'] * rate['per_min'], 60)
    sub = rate['base'] + dist + tm
    fare = max(sub, rate['minimum']) + rate['booking_fee']
    return {'distance': dist, 'time': tm, 'fare': fare}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('regression: minimum before booking fee',
   [{'meters': 0, 'seconds': 30},
    {'base': 250, 'booking_fee': 250, 'minimum': 1000, 'per_km': 125, 'per_min': 35}],
   {'distance': 0, 'fare': 1250, 'time': 18}),
  ('partial repair probe: minimum before booking fee',
   [{'meters': 4, 'seconds': 30},
    {'base': 150, 'booking_fee': 250, 'minimum': 500, 'per_km': 95, 'per_min': 30}],
   {'distance': 0, 'fare': 750, 'time': 15}),
  ('second regression',
   [{'meters': 0, 'seconds': 30},
    {'base': 0, 'booking_fee': 175, 'minimum': 700, 'per_km': 110, 'per_min': 30}],
   {'distance': 0, 'fare': 875, 'time': 15}),
  ('normal control 1',
   [{'meters': 2500, 'seconds': 30},
    {'base': 250, 'booking_fee': 0, 'minimum': 1000, 'per_km': 125, 'per_min': 15}],
   {'distance': 313, 'fare': 1000, 'time': 8}),
  ('normal control 2',
   [{'meters': 0, 'seconds': 61},
    {'base': 0, 'booking_fee': 0, 'minimum': 700, 'per_km': 125, 'per_min': 15}],
   {'distance': 0, 'fare': 700, 'time': 15}),
  ('normal control 3',
   [{'meters': 500, 'seconds': 0},
    {'base': 0, 'booking_fee': 0, 'minimum': 500, 'per_km': 250, 'per_min': 30}],
   {'distance': 125, 'fare': 500, 'time': 0}),
  ('normal control 4',
   [{'meters': 0, 'seconds': 61},
    {'base': 250, 'booking_fee': 0, 'minimum': 500, 'per_km': 110, 'per_min': 35}],
   {'distance': 0, 'fare': 500, 'time': 36})],
 [('regression: minimum before booking fee',
   [{'meters': 2500, 'seconds': 90},
    {'base': 0, 'booking_fee': 250, 'minimum': 700, 'per_km': 125, 'per_min': 15}],
   {'distance': 313, 'fare': 950, 'time': 23}),
  ('partial repair probe: minimum before booking fee',
   [{'meters': 0, 'seconds': 0},
    {'base': 250, 'booking_fee': 175, 'minimum': 1000, 'per_km': 95, 'per_min': 35}],
   {'distance': 0, 'fare': 1175, 'time': 0}),
  ('second regression',
   [{'meters': 0, 'seconds': 90},
    {'base': 250, 'booking_fee': 175, 'minimum': 1000, 'per_km': 110, 'per_min': 30}],
   {'distance': 0, 'fare': 1175, 'time': 45}),
  ('normal control 1',
   [{'meters': 15327, 'seconds': 30},
    {'base': 0, 'booking_fee': 250, 'minimum': 700, 'per_km': 125, 'per_min': 30}],
   {'distance': 1916, 'fare': 2181, 'time': 15}),
  ('normal control 2',
   [{'meters': 500, 'seconds': 1882},
    {'base': 0, 'booking_fee': 0, 'minimum': 500, 'per_km': 250, 'per_min': 25}],
   {'distance': 125, 'fare': 909, 'time': 784}),
  ('normal control 3',
   [{'meters': 500, 'seconds': 61},
    {'base': 250, 'booking_fee': 0, 'minimum': 700, 'per_km': 95, 'per_min': 30}],
   {'distance': 48, 'fare': 700, 'time': 31}),
  ('normal control 4',
   [{'meters': 500, 'seconds': 0},
    {'base': 250, 'booking_fee': 0, 'minimum': 700, 'per_km': 95, 'per_min': 35}],
   {'distance': 48, 'fare': 700, 'time': 0})],
 [('regression: minimum before booking fee',
   [{'meters': 1004, 'seconds': 0},
    {'base': 0, 'booking_fee': 175, 'minimum': 500, 'per_km': 250, 'per_min': 15}],
   {'distance': 251, 'fare': 675, 'time': 0}),
  ('partial repair probe: minimum before booking fee',
   [{'meters': 4, 'seconds': 0},
    {'base': 150, 'booking_fee': 250, 'minimum': 700, 'per_km': 110, 'per_min': 30}],
   {'distance': 0, 'fare': 950, 'time': 0}),
  ('second regression',
   [{'meters': 12, 'seconds': 90},
    {'base': 250, 'booking_fee': 250, 'minimum': 700, 'per_km': 110, 'per_min': 30}],
   {'distance': 1, 'fare': 950, 'time': 45}),
  ('normal control 1',
   [{'meters': 0, 'seconds': 61},
    {'base': 250, 'booking_fee': 0, 'minimum': 500, 'per_km': 110, 'per_min': 15}],
   {'distance': 0, 'fare': 500, 'time': 15}),
  ('normal control 2',
   [{'meters': 6354, 'seconds': 30},
    {'base': 0, 'booking_fee': 0, 'minimum': 500, 'per_km': 110, 'per_min': 35}],
   {'distance': 699, 'fare': 717, 'time': 18}),
  ('normal control 3',
   [{'meters': 4, 'seconds': 61},
    {'base': 250, 'booking_fee': 0, 'minimum': 500, 'per_km': 95, 'per_min': 35}],
   {'distance': 0, 'fare': 500, 'time': 36}),
  ('normal control 4',
   [{'meters': 23665, 'seconds': 30},
    {'base': 0, 'booking_fee': 175, 'minimum': 500, 'per_km': 110, 'per_min': 15}],
   {'distance': 2603, 'fare': 2786, 'time': 8})],
 [('regression: minimum before booking fee',
   [{'meters': 500, 'seconds': 30},
    {'base': 150, 'booking_fee': 175, 'minimum': 1000, 'per_km': 110, 'per_min': 15}],
   {'distance': 55, 'fare': 1175, 'time': 8}),
  ('partial repair probe: minimum before booking fee',
   [{'meters': 0, 'seconds': 1374},
    {'base': 0, 'booking_fee': 175, 'minimum': 700, 'per_km': 110, 'per_min': 15}],
   {'distance': 0, 'fare': 875, 'time': 344}),
  ('second regression',
   [{'meters': 500, 'seconds': 30},
    {'base': 0, 'booking_fee': 175, 'minimum': 500, 'per_km': 110, 'per_min': 35}],
   {'distance': 55, 'fare': 675, 'time': 18}),
  ('normal control 1',
   [{'meters': 1004, 'seconds': 61},
    {'base': 0, 'booking_fee': 0, 'minimum': 500, 'per_km': 95, 'per_min': 15}],
   {'distance': 95, 'fare': 500, 'time': 15}),
  ('normal control 2',
   [{'meters': 0, 'seconds': 30},
    {'base': 150, 'booking_fee': 0, 'minimum': 1000, 'per_km': 125, 'per_min': 30}],
   {'distance': 0, 'fare': 1000, 'time': 15}),
  ('normal control 3',
   [{'meters': 12, 'seconds': 61},
    {'base': 150, 'booking_fee': 0, 'minimum': 500, 'per_km': 110, 'per_min': 15}],
   {'distance': 1, 'fare': 500, 'time': 15}),
  ('normal control 4',
   [{'meters': 24766, 'seconds': 30},
    {'base': 250, 'booking_fee': 250, 'minimum': 1000, 'per_km': 250, 'per_min': 30}],
   {'distance': 6192, 'fare': 6707, 'time': 15})],
 [('regression: minimum before booking fee',
   [{'meters': 500, 'seconds': 61},
    {'base': 150, 'booking_fee': 250, 'minimum': 500, 'per_km': 125, 'per_min': 35}],
   {'distance': 63, 'fare': 750, 'time': 36}),
  ('partial repair probe: minimum before booking fee',
   [{'meters': 500, 'seconds': 90},
    {'base': 0, 'booking_fee': 250, 'minimum': 700, 'per_km': 110, 'per_min': 35}],
   {'distance': 55, 'fare': 950, 'time': 53}),
  ('second regression',
   [{'meters': 2500, 'seconds': 30},
    {'base': 0, 'booking_fee': 175, 'minimum': 700, 'per_km': 250, 'per_min': 15}],
   {'distance': 625, 'fare': 875, 'time': 8}),
  ('normal control 1',
   [{'meters': 4, 'seconds': 2383},
    {'base': 250, 'booking_fee': 0, 'minimum': 700, 'per_km': 250, 'per_min': 35}],
   {'distance': 1, 'fare': 1641, 'time': 1390}),
  ('normal control 2',
   [{'meters': 0, 'seconds': 1117},
    {'base': 250, 'booking_fee': 250, 'minimum': 700, 'per_km': 125, 'per_min': 30}],
   {'distance': 0, 'fare': 1059, 'time': 559}),
  ('normal control 3',
   [{'meters': 0, 'seconds': 30}, {'base': 0, 'booking_fee': 0, 'minimum': 700, 'per_km': 95, 'per_min': 35}],
   {'distance': 0, 'fare': 700, 'time': 18}),
  ('normal control 4',
   [{'meters': 12, 'seconds': 30},
    {'base': 150, 'booking_fee': 0, 'minimum': 500, 'per_km': 110, 'per_min': 15}],
   {'distance': 1, 'fare': 500, 'time': 8})]]
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 fixtureActualExpectedOutcome
regression: minimum before booking fee{'distance': 0, 'fare': 1250, 'time': 18}{'distance': 0, 'fare': 1250, 'time': 18}Passed
partial repair probe: minimum before booking fee{'distance': 0, 'fare': 750, 'time': 15}{'distance': 0, 'fare': 750, 'time': 15}Passed
second regression{'distance': 0, 'fare': 875, 'time': 15}{'distance': 0, 'fare': 875, 'time': 15}Passed
normal control 1{'distance': 313, 'fare': 1000, 'time': 8}{'distance': 313, 'fare': 1000, 'time': 8}Passed
normal control 2{'distance': 0, 'fare': 700, 'time': 15}{'distance': 0, 'fare': 700, 'time': 15}Passed
normal control 3{'distance': 125, 'fare': 500, 'time': 0}{'distance': 125, 'fare': 500, 'time': 0}Passed
normal control 4{'distance': 0, 'fare': 500, 'time': 36}{'distance': 0, 'fare': 500, 'time': 36}Passed

SHA-256 / dc517079c3795314231982fae97b64909f1a51998ac8a1a0b8336a8cc811e731

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 2026-09-29T14:50:39.582794+00:00.

Case digest / 46c866cc0aa02bc9468df282e2d73c480f7f2f04f5ba55395f71bebb1500d32c