FAILURE MAP
← Case archive

FA-94526 / Exam timetabling constraints / Open access

Alternate seating skips the last row of odd-sized halls · case 01

Halls with an odd number of rows lose a row of usable seats.

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

ROOT CAUSE

The row range stops one row early.

THE FAILURE

The row range stops one row early.

Unsuccessful approach: Starting at row 1 uses odd rows and loses seats in single-row rooms.

Case contract

Candidates [id, surname, given, access flag], rooms [room, rows, cols]. Non-access candidates are sorted by case-folded surname, case-folded given name, then id, and take alternate seats (even row and even column indices) room by room in row-major order, labelled room-<row letter><column number>; candidates beyond the seats are UNSEATED. Access candidates go to SEP-1, SEP-2... in the same order. Return id -> seat.

Why this case matters

Seating plans are generated from the timetable's room allocation and must be deterministic and fair.

1 / The failure

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

N = 1
observations = []
def solve(cands, rooms):
    def key(c):
        return (c[1].casefold(), c[2].casefold(), c[0])
    main = sorted([c for c in cands if not c[3]], key=key)
    sep = sorted([c for c in cands if c[3]], key=key)
    seats = []
    for room, rows, cols in rooms:
        for r in range(0, rows - 1, 2):
            for c in range(0, cols, 2):
                seats.append('%s-%s%d' % (room, chr(65 + r), c + 1))
    out = {}
    for k, c in enumerate(main):
        out[c[0]] = seats[k] if k < len(seats) else 'UNSEATED'
    for k, c in enumerate(sep):
        out[c[0]] = 'SEP-%d' % (k + 1)
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('regression: odd row dropped 1',
   [[['C1', 'Strauß', 'Anna', 0], ['C2', 'Strausz', 'Ben', 0]], [['H1', 1, 3]]],
   {'C1': 'H1-A1', 'C2': 'H1-A3'}),
  ('regression variant: odd row dropped 2',
   [[['C43', 'adams', 'Dan', 0], ['C55', 'Öberg', 'Ola', 0], ['C23', 'Mason', 'amy', 0],
     ['C21', 'Mason', 'Amy', 0]],
    [['H0', 1, 1], ['H1', 5, 1]]],
   {'C43': 'H0-A1', 'C21': 'H1-A1', 'C23': 'H1-C1', 'C55': 'H1-E1'}),
  ('partial repair guard 3',
   [[['C05', 'strauss', 'Cara', 0], ['C62', 'Strauß', 'Anna', 1], ['C75', 'Zhou', 'Li', 0],
     ['C85', 'Adams', 'eve', 0]],
    [['H0', 4, 5]]],
   {'C85': 'H0-A1', 'C05': 'H0-A3', 'C75': 'H0-A5', 'C62': 'SEP-1'}),
  ('boundary control 4', [[['C1', 'Adams', 'Eve', 0], ['C2', 'Baker', 'Al', 1]], [['H1', 1, 1]]],
   {'C1': 'H1-A1', 'C2': 'SEP-1'}),
  ('boundary control 5',
   [[['C1', 'Adams', 'Eve', 0], ['C2', 'Baker', 'Al', 0], ['C3', 'Cole', 'Bo', 0]], [['H1', 3, 3]]],
   {'C1': 'H1-A1', 'C2': 'H1-A3', 'C3': 'H1-C1'}),
  ('normal control 6',
   [[['C99', 'Strausz', 'Ben', 0], ['C45', 'Zhou', 'Li', 0], ['C67', 'Mason', 'Zed', 0],
     ['C71', 'Mason', 'amy', 0]],
    [['H0', 3, 1]]],
   {'C71': 'H0-A1', 'C67': 'H0-C1', 'C99': 'UNSEATED', 'C45': 'UNSEATED'}),
  ('normal control 7',
   [[['C10', 'Strausz', 'Ben', 0], ['C79', 'adams', 'Dan', 0], ['C60', 'Zhou', 'Li', 1],
     ['C42', 'strauss', 'Cara', 0], ['C97', 'Adams', 'eve', 0], ['C51', 'Öberg', 'Ola', 0],
     ['C85', 'Mason', 'amy', 1]],
    [['H0', 5, 1], ['H1', 4, 5]]],
   {'C79': 'H0-A1',
    'C97': 'H0-C1',
    'C42': 'H0-E1',
    'C10': 'H1-A1',
    'C51': 'H1-A3',
    'C85': 'SEP-1',
    'C60': 'SEP-2'}),
  ('normal control 8',
   [[['C85', 'Mason', 'amy', 0], ['C98', 'Strauß', 'Anna', 0], ['C12', 'Zhou', 'Li', 0]], [['H0', 2, 1]]],
   {'C85': 'H0-A1', 'C98': 'UNSEATED', 'C12': 'UNSEATED'})],
 [('regression: odd row dropped 1', [[['C1', 'Mason', 'amy', 0], ['C2', 'Mason', 'Ben', 0]], [['H1', 1, 3]]],
   {'C1': 'H1-A1', 'C2': 'H1-A3'}),
  ('regression variant: odd row dropped 2',
   [[['C24', 'Adams', 'eve', 0], ['C93', 'Mason', 'amy', 0], ['C38', 'Mason', 'Amy', 0],
     ['C06', 'Strauß', 'Anna', 1], ['C85', 'adams', 'Dan', 0], ['C18', 'Zhou', 'Li', 1],
     ['C98', 'strauss', 'Cara', 0]],
    [['H0', 5, 1], ['H1', 4, 5]]],
   {'C85': 'H0-A1',
    'C24': 'H0-C1',
    'C38': 'H0-E1',
    'C93': 'H1-A1',
    'C98': 'H1-A3',
    'C06': 'SEP-1',
    'C18': 'SEP-2'}),
  ('partial repair guard 3', [[['C41', 'strauss', 'Cara', 1], ['C29', 'Strauß', 'Anna', 0]], [['H0', 4, 2]]],
   {'C29': 'H0-A1', 'C41': 'SEP-1'}),
  ('boundary control 4', [[['C1', 'Strauß', 'Anna', 0], ['C2', 'Strausz', 'Ben', 0]], [['H1', 1, 3]]],
   {'C1': 'H1-A1', 'C2': 'H1-A3'}),
  ('boundary control 5', [[['C9', 'Mason', 'Amy', 0], ['C1', 'Mason', 'Amy', 0]], [['H1', 2, 3]]],
   {'C1': 'H1-A1', 'C9': 'H1-A3'}),
  ('normal control 6',
   [[['C03', 'Mason', 'amy', 0], ['C88', 'Mason', 'Zed', 0], ['C98', 'Strauß', 'Anna', 1]], [['H0', 5, 1]]],
   {'C03': 'H0-A1', 'C88': 'H0-C1', 'C98': 'SEP-1'}),
  ('normal control 7',
   [[['C17', 'Strauß', 'Anna', 0], ['C46', 'Strausz', 'Ben', 0], ['C87', 'Adams', 'eve', 0],
     ['C91', 'Zhou', 'Li', 0], ['C82', 'Mason', 'Amy', 0], ['C66', 'Mason', 'amy', 0]],
    [['H0', 1, 5], ['H1', 1, 1]]],
   {'C87': 'H0-A1', 'C66': 'H0-A3', 'C82': 'H0-A5', 'C17': 'H1-A1', 'C46': 'UNSEATED', 'C91': 'UNSEATED'}),
  ('normal control 8',
   [[['C49', 'Strausz', 'Ben', 0], ['C35', 'Zhou', 'Li', 0], ['C13', 'Adams', 'eve', 1]], [['H0', 4, 1]]],
   {'C49': 'H0-A1', 'C35': 'H0-C1', 'C13': 'SEP-1'})],
 [('regression: odd row dropped 1',
   [[['C1', 'Adams', 'Eve', 0], ['C2', 'Baker', 'Al', 0], ['C3', 'Cole', 'Bo', 0]], [['H1', 3, 3]]],
   {'C1': 'H1-A1', 'C2': 'H1-A3', 'C3': 'H1-C1'}),
  ('regression variant: odd row dropped 2',
   [[['C58', 'Mason', 'Zed', 0], ['C27', 'adams', 'Dan', 0], ['C98', 'Strausz', 'Ben', 0],
     ['C08', 'Zhou', 'Li', 0], ['C34', 'Öberg', 'Ola', 0]],
    [['H0', 5, 3], ['H1', 5, 2]]],
   {'C27': 'H0-A1', 'C58': 'H0-A3', 'C98': 'H0-C1', 'C08': 'H0-C3', 'C34': 'H0-E1'}),
  ('partial repair guard 3',
   [[['C38', 'Strauß', 'Anna', 0], ['C46', 'Adams', 'eve', 0], ['C83', 'strauss', 'Cara', 0],
     ['C55', 'Zhou', 'Li', 0], ['C21', 'adams', 'Dan', 0], ['C03', 'Mason', 'amy', 0]],
    [['H0', 4, 4]]],
   {'C21': 'H0-A1', 'C46': 'H0-A3', 'C03': 'H0-C1', 'C38': 'H0-C3', 'C83': 'UNSEATED', 'C55': 'UNSEATED'}),
  ('boundary control 4', [[['C1', 'Adams', 'Eve', 0], ['C2', 'Baker', 'Al', 1]], [['H1', 1, 1]]],
   {'C1': 'H1-A1', 'C2': 'SEP-1'}),
  ('normal control 5',
   [[['C75', 'adams', 'Dan', 0], ['C54', 'Mason', 'Amy', 0], ['C48', 'strauss', 'Cara', 0],
     ['C44', 'Strausz', 'Ben', 0], ['C92', 'Strauß', 'Anna', 0], ['C70', 'Adams', 'eve', 0],
     ['C13', 'Mason', 'amy', 1], ['C31', 'Zhou', 'Li', 1]],
    [['H0', 3, 5]]],
   {'C75': 'H0-A1',
    'C70': 'H0-A3',
    'C54': 'H0-A5',
    'C92': 'H0-C1',
    'C48': 'H0-C3',
    'C44': 'H0-C5',
    'C13': 'SEP-1',
    'C31': 'SEP-2'}),
  ('normal control 6',
   [[['C82', 'Öberg', 'Ola', 1], ['C09', 'Mason', 'amy', 0], ['C88', 'Mason', 'Zed', 1],
     ['C24', 'strauss', 'Cara', 0]],
    [['H0', 4, 2]]],
   {'C09': 'H0-A1', 'C24': 'H0-C1', 'C88': 'SEP-1', 'C82': 'SEP-2'}),
  ('normal control 7',
   [[['C21', 'Zhou', 'Li', 0], ['C72', 'Mason', 'amy', 0], ['C36', 'Öberg', 'Ola', 0],
     ['C78', 'adams', 'Dan', 0], ['C80', 'Adams', 'eve', 0], ['C24', 'Mason', 'Amy', 0]],
    [['H0', 2, 5]]],
   {'C78': 'H0-A1', 'C80': 'H0-A3', 'C24': 'H0-A5', 'C72': 'UNSEATED', 'C21': 'UNSEATED', 'C36': 'UNSEATED'}),
  ('normal control 8',
   [[['C73', 'Mason', 'amy', 0], ['C63', 'Strauß', 'Anna', 0], ['C37', 'Strausz', 'Ben', 0],
     ['C80', 'Adams', 'eve', 0], ['C87', 'Mason', 'Zed', 0], ['C44', 'Mason', 'Amy', 0],
     ['C31', 'Öberg', 'Ola', 1], ['C35', 'adams', 'Dan', 0]],
    [['H0', 5, 4]]],
   {'C35': 'H0-A1',
    'C80': 'H0-A3',
    'C44': 'H0-C1',
    'C73': 'H0-C3',
    'C87': 'H0-E1',
    'C63': 'H0-E3',
    'C37': 'UNSEATED',
    'C31': 'SEP-1'})],
 [('regression: odd row dropped 1', [[['C1', 'Adams', 'Eve', 0], ['C2', 'Baker', 'Al', 1]], [['H1', 1, 1]]],
   {'C1': 'H1-A1', 'C2': 'SEP-1'}),
  ('regression variant: odd row dropped 2',
   [[['C23', 'Mason', 'Amy', 1], ['C56', 'Mason', 'amy', 1], ['C92', 'Strauß', 'Anna', 0],
     ['C27', 'Mason', 'Zed', 0], ['C46', 'adams', 'Dan', 0], ['C40', 'Strausz', 'Ben', 0],
     ['C22', 'strauss', 'Cara', 0]],
    [['H0', 1, 5], ['H1', 5, 3]]],
   {'C46': 'H0-A1',
    'C27': 'H0-A3',
    'C92': 'H0-A5',
    'C22': 'H1-A1',
    'C40': 'H1-A3',
    'C23': 'SEP-1',
    'C56': 'SEP-2'}),
  ('partial repair guard 3',
   [[['C27', 'Mason', 'amy', 0], ['C02', 'adams', 'Dan', 0], ['C32', 'Mason', 'Zed', 0],
     ['C55', 'Adams', 'eve', 0]],
    [['H0', 1, 5], ['H1', 5, 2]]],
   {'C02': 'H0-A1', 'C55': 'H0-A3', 'C27': 'H0-A5', 'C32': 'H1-A1'}),
  ('boundary control 4', [[['C1', 'Strauß', 'Anna', 0], ['C2', 'Strausz', 'Ben', 0]], [['H1', 1, 3]]],
   {'C1': 'H1-A1', 'C2': 'H1-A3'}),
  ('boundary control 5', [[['C9', 'Mason', 'Amy', 0], ['C1', 'Mason', 'Amy', 0]], [['H1', 2, 3]]],
   {'C1': 'H1-A1', 'C9': 'H1-A3'}),
  ('normal control 6',
   [[['C72', 'Strausz', 'Ben', 0], ['C92', 'adams', 'Dan', 0], ['C10', 'Strauß', 'Anna', 0],
     ['C11', 'Mason', 'amy', 0], ['C64', 'Mason', 'Amy', 1], ['C73', 'Mason', 'Zed', 0],
     ['C76', 'Öberg', 'Ola', 0], ['C37', 'Zhou', 'Li', 0]],
    [['H0', 5, 1]]],
   {'C92': 'H0-A1',
    'C11': 'H0-C1',
    'C73': 'H0-E1',
    'C10': 'UNSEATED',
    'C72': 'UNSEATED',
    'C37': 'UNSEATED',
    'C76': 'UNSEATED',
    'C64': 'SEP-1'}),
  ('normal control 7',
   [[['C40', 'Strauß', 'Anna', 0], ['C09', 'Mason', 'Zed', 0], ['C26', 'Öberg', 'Ola', 1],
     ['C27', 'adams', 'Dan', 1]],
    [['H0', 4, 2], ['H1', 1, 1]]],
   {'C09': 'H0-A1', 'C40': 'H0-C1', 'C27': 'SEP-1', 'C26': 'SEP-2'}),
  ('normal control 8',
   [[['C89', 'Adams', 'eve', 0], ['C38', 'Mason', 'Amy', 0], ['C52', 'Strausz', 'Ben', 1],
     ['C37', 'strauss', 'Cara', 0], ['C33', 'adams', 'Dan', 0], ['C98', 'Öberg', 'Ola', 0],
     ['C88', 'Zhou', 'Li', 0], ['C78', 'Mason', 'Zed', 1]],
    [['H0', 4, 1]]],
   {'C33': 'H0-A1',
    'C89': 'H0-C1',
    'C38': 'UNSEATED',
    'C37': 'UNSEATED',
    'C88': 'UNSEATED',
    'C98': 'UNSEATED',
    'C78': 'SEP-1',
    'C52': 'SEP-2'})],
 [('regression: odd row dropped 1', [[['C1', 'Adams', 'Eve', 0], ['C2', 'Baker', 'Al', 0]], [['H1', 1, 1]]],
   {'C1': 'H1-A1', 'C2': 'UNSEATED'}),
  ('regression variant: odd row dropped 2',
   [[['C85', 'Mason', 'amy', 0], ['C87', 'Mason', 'Amy', 1], ['C34', 'Zhou', 'Li', 1],
     ['C19', 'Strausz', 'Ben', 0], ['C68', 'adams', 'Dan', 0], ['C60', 'Öberg', 'Ola', 1]],
    [['H0', 1, 3]]],
   {'C68': 'H0-A1', 'C85': 'H0-A3', 'C19': 'UNSEATED', 'C87': 'SEP-1', 'C34': 'SEP-2', 'C60': 'SEP-3'}),
  ('partial repair guard 3',
   [[['C69', 'adams', 'Dan', 0], ['C89', 'Mason', 'Zed', 0], ['C34', 'Mason', 'Amy', 0]],
    [['H0', 4, 3], ['H1', 3, 3]]],
   {'C69': 'H0-A1', 'C34': 'H0-A3', 'C89': 'H0-C1'}),
  ('boundary control 4', [[['C1', 'Adams', 'Eve', 0], ['C2', 'Baker', 'Al', 1]], [['H1', 1, 1]]],
   {'C1': 'H1-A1', 'C2': 'SEP-1'}),
  ('boundary control 5',
   [[['C1', 'Adams', 'Eve', 0], ['C2', 'Baker', 'Al', 0], ['C3', 'Cole', 'Bo', 0]], [['H1', 3, 3]]],
   {'C1': 'H1-A1', 'C2': 'H1-A3', 'C3': 'H1-C1'}),
  ('normal control 6',
   [[['C75', 'adams', 'Dan', 0], ['C54', 'Mason', 'Amy', 0], ['C48', 'strauss', 'Cara', 0],
     ['C44', 'Strausz', 'Ben', 0], ['C92', 'Strauß', 'Anna', 0], ['C70', 'Adams', 'eve', 0],
     ['C13', 'Mason', 'amy', 1], ['C31', 'Zhou', 'Li', 1]],
    [['H0', 3, 5]]],
   {'C75': 'H0-A1',
    'C70': 'H0-A3',
    'C54': 'H0-A5',
    'C92': 'H0-C1',
    'C48': 'H0-C3',
    'C44': 'H0-C5',
    'C13': 'SEP-1',
    'C31': 'SEP-2'}),
  ('normal control 7',
   [[['C03', 'strauss', 'Cara', 0], ['C88', 'adams', 'Dan', 0], ['C31', 'Zhou', 'Li', 1],
     ['C06', 'Adams', 'eve', 0], ['C32', 'Mason', 'Zed', 0]],
    [['H0', 4, 3]]],
   {'C88': 'H0-A1', 'C06': 'H0-A3', 'C32': 'H0-C1', 'C03': 'H0-C3', 'C31': 'SEP-1'}),
  ('normal control 8',
   [[['C55', 'adams', 'Dan', 0], ['C13', 'Öberg', 'Ola', 0]], [['H0', 2, 2], ['H1', 2, 5]]],
   {'C55': 'H0-A1', 'C13': 'H1-A1'})]]
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: odd row dropped 1{'C1': 'UNSEATED', 'C2': 'UNSEATED'}{'C1': 'H1-A1', 'C2': 'H1-A3'}Failed
regression variant: odd row dropped 2{'C21': 'H1-C1', 'C23': 'UNSEATED', 'C43': 'H1-A1', 'C55': 'UNSEATED'}{'C21': 'H1-A1', 'C23': 'H1-C1', 'C43': 'H0-A1', 'C55': 'H1-E1'}Failed
partial repair guard 3{'C05': 'H0-A3', 'C62': 'SEP-1', 'C75': 'H0-A5', 'C85': 'H0-A1'}{'C05': 'H0-A3', 'C62': 'SEP-1', 'C75': 'H0-A5', 'C85': 'H0-A1'}Passed
boundary control 4{'C1': 'UNSEATED', 'C2': 'SEP-1'}{'C1': 'H1-A1', 'C2': 'SEP-1'}Failed
boundary control 5{'C1': 'H1-A1', 'C2': 'H1-A3', 'C3': 'UNSEATED'}{'C1': 'H1-A1', 'C2': 'H1-A3', 'C3': 'H1-C1'}Failed
normal control 6{'C45': 'UNSEATED', 'C67': 'UNSEATED', 'C71': 'H0-A1', 'C99': 'UNSEATED'}{'C45': 'UNSEATED', 'C67': 'H0-C1', 'C71': 'H0-A1', 'C99': 'UNSEATED'}Failed
normal control 7{'C10': 'H1-A3', 'C42': 'H1-A1', 'C51': 'H1-A5', 'C60': 'SEP-2', 'C79': 'H0-A1', 'C85': 'SEP-1', 'C97': 'H0-C1'}{'C10': 'H1-A1', 'C42': 'H0-E1', 'C51': 'H1-A3', 'C60': 'SEP-2', 'C79': 'H0-A1', 'C85': 'SEP-1', 'C97': 'H0-C1'}Failed
normal control 8{'C12': 'UNSEATED', 'C85': 'H0-A1', 'C98': 'UNSEATED'}{'C12': 'UNSEATED', 'C85': 'H0-A1', 'C98': 'UNSEATED'}Passed

SHA-256 / 74726477201c60c070c41cc0a5fb5a533430dedfdada24b810357ed244b575fe

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(cands, rooms):
    def key(c):
        return (c[1].casefold(), c[2].casefold(), c[0])
    main = sorted([c for c in cands if not c[3]], key=key)
    sep = sorted([c for c in cands if c[3]], key=key)
    seats = []
    for room, rows, cols in rooms:
        for r in range(1, rows, 2):
            for c in range(0, cols, 2):
                seats.append('%s-%s%d' % (room, chr(65 + r), c + 1))
    out = {}
    for k, c in enumerate(main):
        out[c[0]] = seats[k] if k < len(seats) else 'UNSEATED'
    for k, c in enumerate(sep):
        out[c[0]] = 'SEP-%d' % (k + 1)
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('regression: odd row dropped 1',
   [[['C1', 'Strauß', 'Anna', 0], ['C2', 'Strausz', 'Ben', 0]], [['H1', 1, 3]]],
   {'C1': 'H1-A1', 'C2': 'H1-A3'}),
  ('regression variant: odd row dropped 2',
   [[['C43', 'adams', 'Dan', 0], ['C55', 'Öberg', 'Ola', 0], ['C23', 'Mason', 'amy', 0],
     ['C21', 'Mason', 'Amy', 0]],
    [['H0', 1, 1], ['H1', 5, 1]]],
   {'C43': 'H0-A1', 'C21': 'H1-A1', 'C23': 'H1-C1', 'C55': 'H1-E1'}),
  ('partial repair guard 3',
   [[['C05', 'strauss', 'Cara', 0], ['C62', 'Strauß', 'Anna', 1], ['C75', 'Zhou', 'Li', 0],
     ['C85', 'Adams', 'eve', 0]],
    [['H0', 4, 5]]],
   {'C85': 'H0-A1', 'C05': 'H0-A3', 'C75': 'H0-A5', 'C62': 'SEP-1'}),
  ('boundary control 4', [[['C1', 'Adams', 'Eve', 0], ['C2', 'Baker', 'Al', 1]], [['H1', 1, 1]]],
   {'C1': 'H1-A1', 'C2': 'SEP-1'}),
  ('boundary control 5',
   [[['C1', 'Adams', 'Eve', 0], ['C2', 'Baker', 'Al', 0], ['C3', 'Cole', 'Bo', 0]], [['H1', 3, 3]]],
   {'C1': 'H1-A1', 'C2': 'H1-A3', 'C3': 'H1-C1'}),
  ('normal control 6',
   [[['C99', 'Strausz', 'Ben', 0], ['C45', 'Zhou', 'Li', 0], ['C67', 'Mason', 'Zed', 0],
     ['C71', 'Mason', 'amy', 0]],
    [['H0', 3, 1]]],
   {'C71': 'H0-A1', 'C67': 'H0-C1', 'C99': 'UNSEATED', 'C45': 'UNSEATED'}),
  ('normal control 7',
   [[['C10', 'Strausz', 'Ben', 0], ['C79', 'adams', 'Dan', 0], ['C60', 'Zhou', 'Li', 1],
     ['C42', 'strauss', 'Cara', 0], ['C97', 'Adams', 'eve', 0], ['C51', 'Öberg', 'Ola', 0],
     ['C85', 'Mason', 'amy', 1]],
    [['H0', 5, 1], ['H1', 4, 5]]],
   {'C79': 'H0-A1',
    'C97': 'H0-C1',
    'C42': 'H0-E1',
    'C10': 'H1-A1',
    'C51': 'H1-A3',
    'C85': 'SEP-1',
    'C60': 'SEP-2'}),
  ('normal control 8',
   [[['C85', 'Mason', 'amy', 0], ['C98', 'Strauß', 'Anna', 0], ['C12', 'Zhou', 'Li', 0]], [['H0', 2, 1]]],
   {'C85': 'H0-A1', 'C98': 'UNSEATED', 'C12': 'UNSEATED'})],
 [('regression: odd row dropped 1', [[['C1', 'Mason', 'amy', 0], ['C2', 'Mason', 'Ben', 0]], [['H1', 1, 3]]],
   {'C1': 'H1-A1', 'C2': 'H1-A3'}),
  ('regression variant: odd row dropped 2',
   [[['C24', 'Adams', 'eve', 0], ['C93', 'Mason', 'amy', 0], ['C38', 'Mason', 'Amy', 0],
     ['C06', 'Strauß', 'Anna', 1], ['C85', 'adams', 'Dan', 0], ['C18', 'Zhou', 'Li', 1],
     ['C98', 'strauss', 'Cara', 0]],
    [['H0', 5, 1], ['H1', 4, 5]]],
   {'C85': 'H0-A1',
    'C24': 'H0-C1',
    'C38': 'H0-E1',
    'C93': 'H1-A1',
    'C98': 'H1-A3',
    'C06': 'SEP-1',
    'C18': 'SEP-2'}),
  ('partial repair guard 3', [[['C41', 'strauss', 'Cara', 1], ['C29', 'Strauß', 'Anna', 0]], [['H0', 4, 2]]],
   {'C29': 'H0-A1', 'C41': 'SEP-1'}),
  ('boundary control 4', [[['C1', 'Strauß', 'Anna', 0], ['C2', 'Strausz', 'Ben', 0]], [['H1', 1, 3]]],
   {'C1': 'H1-A1', 'C2': 'H1-A3'}),
  ('boundary control 5', [[['C9', 'Mason', 'Amy', 0], ['C1', 'Mason', 'Amy', 0]], [['H1', 2, 3]]],
   {'C1': 'H1-A1', 'C9': 'H1-A3'}),
  ('normal control 6',
   [[['C03', 'Mason', 'amy', 0], ['C88', 'Mason', 'Zed', 0], ['C98', 'Strauß', 'Anna', 1]], [['H0', 5, 1]]],
   {'C03': 'H0-A1', 'C88': 'H0-C1', 'C98': 'SEP-1'}),
  ('normal control 7',
   [[['C17', 'Strauß', 'Anna', 0], ['C46', 'Strausz', 'Ben', 0], ['C87', 'Adams', 'eve', 0],
     ['C91', 'Zhou', 'Li', 0], ['C82', 'Mason', 'Amy', 0], ['C66', 'Mason', 'amy', 0]],
    [['H0', 1, 5], ['H1', 1, 1]]],
   {'C87': 'H0-A1', 'C66': 'H0-A3', 'C82': 'H0-A5', 'C17': 'H1-A1', 'C46': 'UNSEATED', 'C91': 'UNSEATED'}),
  ('normal control 8',
   [[['C49', 'Strausz', 'Ben', 0], ['C35', 'Zhou', 'Li', 0], ['C13', 'Adams', 'eve', 1]], [['H0', 4, 1]]],
   {'C49': 'H0-A1', 'C35': 'H0-C1', 'C13': 'SEP-1'})],
 [('regression: odd row dropped 1',
   [[['C1', 'Adams', 'Eve', 0], ['C2', 'Baker', 'Al', 0], ['C3', 'Cole', 'Bo', 0]], [['H1', 3, 3]]],
   {'C1': 'H1-A1', 'C2': 'H1-A3', 'C3': 'H1-C1'}),
  ('regression variant: odd row dropped 2',
   [[['C58', 'Mason', 'Zed', 0], ['C27', 'adams', 'Dan', 0], ['C98', 'Strausz', 'Ben', 0],
     ['C08', 'Zhou', 'Li', 0], ['C34', 'Öberg', 'Ola', 0]],
    [['H0', 5, 3], ['H1', 5, 2]]],
   {'C27': 'H0-A1', 'C58': 'H0-A3', 'C98': 'H0-C1', 'C08': 'H0-C3', 'C34': 'H0-E1'}),
  ('partial repair guard 3',
   [[['C38', 'Strauß', 'Anna', 0], ['C46', 'Adams', 'eve', 0], ['C83', 'strauss', 'Cara', 0],
     ['C55', 'Zhou', 'Li', 0], ['C21', 'adams', 'Dan', 0], ['C03', 'Mason', 'amy', 0]],
    [['H0', 4, 4]]],
   {'C21': 'H0-A1', 'C46': 'H0-A3', 'C03': 'H0-C1', 'C38': 'H0-C3', 'C83': 'UNSEATED', 'C55': 'UNSEATED'}),
  ('boundary control 4', [[['C1', 'Adams', 'Eve', 0], ['C2', 'Baker', 'Al', 1]], [['H1', 1, 1]]],
   {'C1': 'H1-A1', 'C2': 'SEP-1'}),
  ('normal control 5',
   [[['C75', 'adams', 'Dan', 0], ['C54', 'Mason', 'Amy', 0], ['C48', 'strauss', 'Cara', 0],
     ['C44', 'Strausz', 'Ben', 0], ['C92', 'Strauß', 'Anna', 0], ['C70', 'Adams', 'eve', 0],
     ['C13', 'Mason', 'amy', 1], ['C31', 'Zhou', 'Li', 1]],
    [['H0', 3, 5]]],
   {'C75': 'H0-A1',
    'C70': 'H0-A3',
    'C54': 'H0-A5',
    'C92': 'H0-C1',
    'C48': 'H0-C3',
    'C44': 'H0-C5',
    'C13': 'SEP-1',
    'C31': 'SEP-2'}),
  ('normal control 6',
   [[['C82', 'Öberg', 'Ola', 1], ['C09', 'Mason', 'amy', 0], ['C88', 'Mason', 'Zed', 1],
     ['C24', 'strauss', 'Cara', 0]],
    [['H0', 4, 2]]],
   {'C09': 'H0-A1', 'C24': 'H0-C1', 'C88': 'SEP-1', 'C82': 'SEP-2'}),
  ('normal control 7',
   [[['C21', 'Zhou', 'Li', 0], ['C72', 'Mason', 'amy', 0], ['C36', 'Öberg', 'Ola', 0],
     ['C78', 'adams', 'Dan', 0], ['C80', 'Adams', 'eve', 0], ['C24', 'Mason', 'Amy', 0]],
    [['H0', 2, 5]]],
   {'C78': 'H0-A1', 'C80': 'H0-A3', 'C24': 'H0-A5', 'C72': 'UNSEATED', 'C21': 'UNSEATED', 'C36': 'UNSEATED'}),
  ('normal control 8',
   [[['C73', 'Mason', 'amy', 0], ['C63', 'Strauß', 'Anna', 0], ['C37', 'Strausz', 'Ben', 0],
     ['C80', 'Adams', 'eve', 0], ['C87', 'Mason', 'Zed', 0], ['C44', 'Mason', 'Amy', 0],
     ['C31', 'Öberg', 'Ola', 1], ['C35', 'adams', 'Dan', 0]],
    [['H0', 5, 4]]],
   {'C35': 'H0-A1',
    'C80': 'H0-A3',
    'C44': 'H0-C1',
    'C73': 'H0-C3',
    'C87': 'H0-E1',
    'C63': 'H0-E3',
    'C37': 'UNSEATED',
    'C31': 'SEP-1'})],
 [('regression: odd row dropped 1', [[['C1', 'Adams', 'Eve', 0], ['C2', 'Baker', 'Al', 1]], [['H1', 1, 1]]],
   {'C1': 'H1-A1', 'C2': 'SEP-1'}),
  ('regression variant: odd row dropped 2',
   [[['C23', 'Mason', 'Amy', 1], ['C56', 'Mason', 'amy', 1], ['C92', 'Strauß', 'Anna', 0],
     ['C27', 'Mason', 'Zed', 0], ['C46', 'adams', 'Dan', 0], ['C40', 'Strausz', 'Ben', 0],
     ['C22', 'strauss', 'Cara', 0]],
    [['H0', 1, 5], ['H1', 5, 3]]],
   {'C46': 'H0-A1',
    'C27': 'H0-A3',
    'C92': 'H0-A5',
    'C22': 'H1-A1',
    'C40': 'H1-A3',
    'C23': 'SEP-1',
    'C56': 'SEP-2'}),
  ('partial repair guard 3',
   [[['C27', 'Mason', 'amy', 0], ['C02', 'adams', 'Dan', 0], ['C32', 'Mason', 'Zed', 0],
     ['C55', 'Adams', 'eve', 0]],
    [['H0', 1, 5], ['H1', 5, 2]]],
   {'C02': 'H0-A1', 'C55': 'H0-A3', 'C27': 'H0-A5', 'C32': 'H1-A1'}),
  ('boundary control 4', [[['C1', 'Strauß', 'Anna', 0], ['C2', 'Strausz', 'Ben', 0]], [['H1', 1, 3]]],
   {'C1': 'H1-A1', 'C2': 'H1-A3'}),
  ('boundary control 5', [[['C9', 'Mason', 'Amy', 0], ['C1', 'Mason', 'Amy', 0]], [['H1', 2, 3]]],
   {'C1': 'H1-A1', 'C9': 'H1-A3'}),
  ('normal control 6',
   [[['C72', 'Strausz', 'Ben', 0], ['C92', 'adams', 'Dan', 0], ['C10', 'Strauß', 'Anna', 0],
     ['C11', 'Mason', 'amy', 0], ['C64', 'Mason', 'Amy', 1], ['C73', 'Mason', 'Zed', 0],
     ['C76', 'Öberg', 'Ola', 0], ['C37', 'Zhou', 'Li', 0]],
    [['H0', 5, 1]]],
   {'C92': 'H0-A1',
    'C11': 'H0-C1',
    'C73': 'H0-E1',
    'C10': 'UNSEATED',
    'C72': 'UNSEATED',
    'C37': 'UNSEATED',
    'C76': 'UNSEATED',
    'C64': 'SEP-1'}),
  ('normal control 7',
   [[['C40', 'Strauß', 'Anna', 0], ['C09', 'Mason', 'Zed', 0], ['C26', 'Öberg', 'Ola', 1],
     ['C27', 'adams', 'Dan', 1]],
    [['H0', 4, 2], ['H1', 1, 1]]],
   {'C09': 'H0-A1', 'C40': 'H0-C1', 'C27': 'SEP-1', 'C26': 'SEP-2'}),
  ('normal control 8',
   [[['C89', 'Adams', 'eve', 0], ['C38', 'Mason', 'Amy', 0], ['C52', 'Strausz', 'Ben', 1],
     ['C37', 'strauss', 'Cara', 0], ['C33', 'adams', 'Dan', 0], ['C98', 'Öberg', 'Ola', 0],
     ['C88', 'Zhou', 'Li', 0], ['C78', 'Mason', 'Zed', 1]],
    [['H0', 4, 1]]],
   {'C33': 'H0-A1',
    'C89': 'H0-C1',
    'C38': 'UNSEATED',
    'C37': 'UNSEATED',
    'C88': 'UNSEATED',
    'C98': 'UNSEATED',
    'C78': 'SEP-1',
    'C52': 'SEP-2'})],
 [('regression: odd row dropped 1', [[['C1', 'Adams', 'Eve', 0], ['C2', 'Baker', 'Al', 0]], [['H1', 1, 1]]],
   {'C1': 'H1-A1', 'C2': 'UNSEATED'}),
  ('regression variant: odd row dropped 2',
   [[['C85', 'Mason', 'amy', 0], ['C87', 'Mason', 'Amy', 1], ['C34', 'Zhou', 'Li', 1],
     ['C19', 'Strausz', 'Ben', 0], ['C68', 'adams', 'Dan', 0], ['C60', 'Öberg', 'Ola', 1]],
    [['H0', 1, 3]]],
   {'C68': 'H0-A1', 'C85': 'H0-A3', 'C19': 'UNSEATED', 'C87': 'SEP-1', 'C34': 'SEP-2', 'C60': 'SEP-3'}),
  ('partial repair guard 3',
   [[['C69', 'adams', 'Dan', 0], ['C89', 'Mason', 'Zed', 0], ['C34', 'Mason', 'Amy', 0]],
    [['H0', 4, 3], ['H1', 3, 3]]],
   {'C69': 'H0-A1', 'C34': 'H0-A3', 'C89': 'H0-C1'}),
  ('boundary control 4', [[['C1', 'Adams', 'Eve', 0], ['C2', 'Baker', 'Al', 1]], [['H1', 1, 1]]],
   {'C1': 'H1-A1', 'C2': 'SEP-1'}),
  ('boundary control 5',
   [[['C1', 'Adams', 'Eve', 0], ['C2', 'Baker', 'Al', 0], ['C3', 'Cole', 'Bo', 0]], [['H1', 3, 3]]],
   {'C1': 'H1-A1', 'C2': 'H1-A3', 'C3': 'H1-C1'}),
  ('normal control 6',
   [[['C75', 'adams', 'Dan', 0], ['C54', 'Mason', 'Amy', 0], ['C48', 'strauss', 'Cara', 0],
     ['C44', 'Strausz', 'Ben', 0], ['C92', 'Strauß', 'Anna', 0], ['C70', 'Adams', 'eve', 0],
     ['C13', 'Mason', 'amy', 1], ['C31', 'Zhou', 'Li', 1]],
    [['H0', 3, 5]]],
   {'C75': 'H0-A1',
    'C70': 'H0-A3',
    'C54': 'H0-A5',
    'C92': 'H0-C1',
    'C48': 'H0-C3',
    'C44': 'H0-C5',
    'C13': 'SEP-1',
    'C31': 'SEP-2'}),
  ('normal control 7',
   [[['C03', 'strauss', 'Cara', 0], ['C88', 'adams', 'Dan', 0], ['C31', 'Zhou', 'Li', 1],
     ['C06', 'Adams', 'eve', 0], ['C32', 'Mason', 'Zed', 0]],
    [['H0', 4, 3]]],
   {'C88': 'H0-A1', 'C06': 'H0-A3', 'C32': 'H0-C1', 'C03': 'H0-C3', 'C31': 'SEP-1'}),
  ('normal control 8',
   [[['C55', 'adams', 'Dan', 0], ['C13', 'Öberg', 'Ola', 0]], [['H0', 2, 2], ['H1', 2, 5]]],
   {'C55': 'H0-A1', 'C13': 'H1-A1'})]]
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: odd row dropped 1{'C1': 'UNSEATED', 'C2': 'UNSEATED'}{'C1': 'H1-A1', 'C2': 'H1-A3'}Failed
regression variant: odd row dropped 2{'C21': 'H1-D1', 'C23': 'UNSEATED', 'C43': 'H1-B1', 'C55': 'UNSEATED'}{'C21': 'H1-A1', 'C23': 'H1-C1', 'C43': 'H0-A1', 'C55': 'H1-E1'}Failed
partial repair guard 3{'C05': 'H0-B3', 'C62': 'SEP-1', 'C75': 'H0-B5', 'C85': 'H0-B1'}{'C05': 'H0-A3', 'C62': 'SEP-1', 'C75': 'H0-A5', 'C85': 'H0-A1'}Failed
boundary control 4{'C1': 'UNSEATED', 'C2': 'SEP-1'}{'C1': 'H1-A1', 'C2': 'SEP-1'}Failed
boundary control 5{'C1': 'H1-B1', 'C2': 'H1-B3', 'C3': 'UNSEATED'}{'C1': 'H1-A1', 'C2': 'H1-A3', 'C3': 'H1-C1'}Failed
normal control 6{'C45': 'UNSEATED', 'C67': 'UNSEATED', 'C71': 'H0-B1', 'C99': 'UNSEATED'}{'C45': 'UNSEATED', 'C67': 'H0-C1', 'C71': 'H0-A1', 'C99': 'UNSEATED'}Failed
normal control 7{'C10': 'H1-B3', 'C42': 'H1-B1', 'C51': 'H1-B5', 'C60': 'SEP-2', 'C79': 'H0-B1', 'C85': 'SEP-1', 'C97': 'H0-D1'}{'C10': 'H1-A1', 'C42': 'H0-E1', 'C51': 'H1-A3', 'C60': 'SEP-2', 'C79': 'H0-A1', 'C85': 'SEP-1', 'C97': 'H0-C1'}Failed
normal control 8{'C12': 'UNSEATED', 'C85': 'H0-B1', 'C98': 'UNSEATED'}{'C12': 'UNSEATED', 'C85': 'H0-A1', 'C98': 'UNSEATED'}Failed

SHA-256 / 0e4a2073f49bdc019cf0743b962ede5747a947c13e40fa15ea7876807f511295

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.

Every case sharing this mechanism uses the same contract and the same repair, so this one record is held back for all of them.

Member access is invitation-based. Sign in with your invited account to inspect the repair.

Sign in to the archive ↗

Verification & scope

Stipulated toy exam-timetabling rule set for a bounded model; it does not claim conformance with any institution's regulations or a benchmark specification, and it performs no search or optimisation. 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 2026-09-29T14:52:05.231030+00:00.

Case digest / b105d447ec7bc2e130cceb68f46c2a423eb9fb14275a73b749449fb6f748cf96