FAILURE MAP
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FA-86406 / Procedural level generation constraints / Open access

Key and lock solvability: Doors are one-way · case 01

Rooms listed on the far side of a door are unreachable.

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

ROOT CAUSE

Door edges are only walked from the first listed room.

VERIFIED REPAIR

Restore `for u, v in ((a, b), (b, a)):` at the door direction step.

Unsuccessful approach: Walking only the reverse direction breaks doors listed the other way.

Case contract

rooms maps room -> keys lying there; edges [a, b, lock] are two-way doors, lock None or a key colour. Keys are never consumed. Starting in start, repeatedly pick up keys in visited rooms and walk through doors that are open or whose key is held, until nothing changes. Returns {solvable: goal visited, keys: sorted keys held, visited: count}.

Why this case matters

Procedural generators silently emit unplayable or unfair levels when a single constraint check uses the wrong boundary, axis, neighborhood or update order; the defect is visible in exact generated geometry.

1 / The failure

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

N = 1
observations = []
def solve(rooms, edges, start, goal):
    have = set()
    seen = {start}
    changed = True
    while changed:
        changed = False
        for r in list(seen):
            for k in rooms.get(r, []):
                if k not in have:
                    have.add(k)
                    changed = True
        for a, b, lock in edges:
            for u, v in ((a, b),):
                if u in seen and v not in seen and (lock is None or lock in have):
                    seen.add(v)
                    changed = True
    return {'solvable': goal in seen, 'keys': sorted(have), 'visited': len(seen)}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = [[('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('fault site door direction #1',
   [{'r0': ['gold'], 'r2': ['blue']},
    [['r2', 'r1', 'gold'],
     ['r3', 'r1', 'blue'],
     ['r1', 'r3', None],
     ['r1', 'r0', None],
     ['r2', 'r3', 'blue']],
    'r0',
    'r3'],
   {'solvable': True, 'keys': ['blue', 'gold'], 'visited': 4}),
  ('fault site door direction #2',
   [{'r0': ['red'], 'r3': ['gold']},
    [['r4', 'r2', None], ['r0', 'r1', 'blue'], ['r2', 'r0', None], ['r2', 'r3', 'gold']],
    'r0',
    'r4'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('partial repair boundary #1',
   [{'r0': ['gold'], 'r1': ['red'], 'r2': ['gold']},
    [['r0', 'r1', 'red'], ['r2', 'r1', 'red'], ['r0', 'r2', None]],
    'r0',
    'r2'],
   {'solvable': True, 'keys': ['gold'], 'visited': 2}),
  ('regression door direction #1',
   [{'r0': ['red'], 'r1': ['gold'], 'r4': ['gold'], 'r5': ['blue'], 'r6': ['red']},
    [['r1', 'r2', 'blue'],
     ['r0', 'r2', 'red'],
     ['r0', 'r1', 'blue'],
     ['r3', 'r6', 'gold'],
     ['r4', 'r0', None],
     ['r3', 'r2', 'blue'],
     ['r2', 'r5', None]],
    'r0',
    'r6'],
   {'solvable': True, 'keys': ['blue', 'gold', 'red'], 'visited': 7}),
  ('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('control #1', [{}, [['r0', 'r1', 'blue']], 'r0', 'r1'], {'solvable': False, 'keys': [], 'visited': 1})],
 [('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('fault site door direction #1',
   [{'r0': ['red'], 'r3': ['gold']},
    [['r4', 'r2', None], ['r0', 'r1', 'blue'], ['r2', 'r0', None], ['r2', 'r3', 'gold']],
    'r0',
    'r4'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('fault site door direction #2',
   [{'r4': ['red']},
    [['r3', 'r1', 'gold'], ['r3', 'r4', 'blue'], ['r2', 'r1', None], ['r1', 'r0', None]],
    'r0',
    'r3'],
   {'solvable': False, 'keys': [], 'visited': 3}),
  ('regression door direction #1',
   [{'r0': ['red'], 'r1': ['gold'], 'r4': ['gold'], 'r5': ['blue'], 'r6': ['red']},
    [['r1', 'r2', 'blue'],
     ['r0', 'r2', 'red'],
     ['r0', 'r1', 'blue'],
     ['r3', 'r6', 'gold'],
     ['r4', 'r0', None],
     ['r3', 'r2', 'blue'],
     ['r2', 'r5', None]],
    'r0',
    'r6'],
   {'solvable': True, 'keys': ['blue', 'gold', 'red'], 'visited': 7}),
  ('partial repair boundary #1',
   [{'r0': ['red']}, [['r0', 'r1', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': ['red'], 'visited': 2}),
  ('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('control #1', [{}, [['r0', 'r1', 'blue']], 'r0', 'r1'], {'solvable': False, 'keys': [], 'visited': 1})],
 [('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('regression door direction #1',
   [{'r0': ['red'], 'r1': ['gold'], 'r4': ['gold'], 'r5': ['blue'], 'r6': ['red']},
    [['r1', 'r2', 'blue'],
     ['r0', 'r2', 'red'],
     ['r0', 'r1', 'blue'],
     ['r3', 'r6', 'gold'],
     ['r4', 'r0', None],
     ['r3', 'r2', 'blue'],
     ['r2', 'r5', None]],
    'r0',
    'r6'],
   {'solvable': True, 'keys': ['blue', 'gold', 'red'], 'visited': 7}),
  ('fault site door direction #1',
   [{'r3': ['blue'], 'r4': ['gold']},
    [['r4', 'r1', 'blue'],
     ['r5', 'r3', None],
     ['r5', 'r4', 'red'],
     ['r1', 'r0', 'gold'],
     ['r0', 'r2', 'blue'],
     ['r4', 'r0', None],
     ['r3', 'r2', None]],
    'r0',
    'r4'],
   {'solvable': True, 'keys': ['gold'], 'visited': 3}),
  ('regression door direction #2',
   [{'r0': ['blue'], 'r3': ['red']},
    [['r1', 'r0', None],
     ['r5', 'r3', None],
     ['r1', 'r2', 'red'],
     ['r3', 'r2', 'red'],
     ['r0', 'r4', 'gold'],
     ['r3', 'r1', None],
     ['r0', 'r5', 'gold']],
    'r0',
    'r5'],
   {'solvable': True, 'keys': ['blue', 'red'], 'visited': 5}),
  ('regression door direction #3',
   [{'r1': ['red']},
    [['r3', 'r2', 'gold'], ['r1', 'r3', 'red'], ['r1', 'r0', 'gold'], ['r2', 'r0', None], ['r1', 'r2', None]],
    'r0',
    'r3'],
   {'solvable': True, 'keys': ['red'], 'visited': 4}),
  ('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('control #1',
   [{'r1': ['red'], 'r2': ['gold']},
    [['r1', 'r2', 'blue'], ['r1', 'r0', 'red'], ['r4', 'r2', 'blue'], ['r1', 'r3', None]],
    'r0',
    'r2'],
   {'solvable': False, 'keys': [], 'visited': 1})],
 [('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('fault site door direction #1',
   [{'r0': ['blue'], 'r1': ['gold']},
    [['r0', 'r1', 'red'], ['r1', 'r0', 'blue'], ['r0', 'r1', 'red']],
    'r0',
    'r1'],
   {'solvable': True, 'keys': ['blue', 'gold'], 'visited': 2}),
  ('regression door direction #1',
   [{'r0': ['blue'], 'r3': ['red']},
    [['r1', 'r0', None],
     ['r5', 'r3', None],
     ['r1', 'r2', 'red'],
     ['r3', 'r2', 'red'],
     ['r0', 'r4', 'gold'],
     ['r3', 'r1', None],
     ['r0', 'r5', 'gold']],
    'r0',
    'r5'],
   {'solvable': True, 'keys': ['blue', 'red'], 'visited': 5}),
  ('partial repair boundary #1',
   [{'r3': ['red'], 'r5': ['red']},
    [['r1', 'r3', 'gold'],
     ['r2', 'r3', 'blue'],
     ['r2', 'r1', 'blue'],
     ['r0', 'r1', None],
     ['r2', 'r4', 'gold'],
     ['r5', 'r4', 'red']],
    'r0',
    'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('regression door direction #2',
   [{'r1': ['red'], 'r4': ['blue'], 'r6': ['gold']},
    [['r1', 'r0', 'blue'],
     ['r2', 'r6', 'blue'],
     ['r5', 'r4', None],
     ['r0', 'r2', 'gold'],
     ['r1', 'r3', None],
     ['r0', 'r4', None]],
    'r0',
    'r5'],
   {'solvable': True, 'keys': ['blue', 'red'], 'visited': 5}),
  ('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('control #1',
   [{'r2': ['red']},
    [['r1', 'r0', 'blue'], ['r1', 'r2', None], ['r1', 'r2', 'blue'], ['r1', 'r2', 'blue']],
    'r0',
    'r2'],
   {'solvable': False, 'keys': [], 'visited': 1})],
 [('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('regression door direction #1',
   [{'r1': ['red']},
    [['r3', 'r2', 'gold'], ['r1', 'r3', 'red'], ['r1', 'r0', 'gold'], ['r2', 'r0', None], ['r1', 'r2', None]],
    'r0',
    'r3'],
   {'solvable': True, 'keys': ['red'], 'visited': 4}),
  ('fault site door direction #1',
   [{'r4': ['blue']},
    [['r6', 'r1', None],
     ['r1', 'r0', None],
     ['r1', 'r5', 'blue'],
     ['r2', 'r1', 'gold'],
     ['r4', 'r0', 'blue'],
     ['r3', 'r6', None],
     ['r4', 'r5', None],
     ['r3', 'r1', 'gold']],
    'r0',
    'r2'],
   {'solvable': False, 'keys': [], 'visited': 4}),
  ('regression door direction #2',
   [{'r0': ['gold'], 'r2': ['gold'], 'r3': ['red'], 'r4': ['red']},
    [['r0', 'r1', None],
     ['r1', 'r2', 'blue'],
     ['r6', 'r1', None],
     ['r5', 'r0', 'blue'],
     ['r3', 'r2', 'gold'],
     ['r4', 'r0', None]],
    'r0',
    'r3'],
   {'solvable': False, 'keys': ['gold', 'red'], 'visited': 4}),
  ('partial repair boundary #1',
   [{'r0': ['red']}, [['r0', 'r1', 'red'], ['r0', 'r1', None], ['r1', 'r0', 'blue']], 'r0', 'r1'],
   {'solvable': True, 'keys': ['red'], 'visited': 2}),
  ('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('control #1',
   [{}, [['r1', 'r0', 'red'], ['r2', 'r1', None]], 'r0', 'r1'],
   {'solvable': False, 'keys': [], 'visited': 1})]]
for label, args, expected in cases[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
reverse listed door #1{'keys': [], 'solvable': False, 'visited': 1}{'keys': [], 'solvable': True, 'visited': 2}Failed
key behind first door #1{'keys': ['red'], 'solvable': True, 'visited': 3}{'keys': ['red'], 'solvable': True, 'visited': 3}Passed
fault site door direction #1{'keys': ['gold'], 'solvable': False, 'visited': 1}{'keys': ['blue', 'gold'], 'solvable': True, 'visited': 4}Failed
fault site door direction #2{'keys': ['red'], 'solvable': False, 'visited': 1}{'keys': ['red'], 'solvable': True, 'visited': 3}Failed
partial repair boundary #1{'keys': ['gold'], 'solvable': True, 'visited': 2}{'keys': ['gold'], 'solvable': True, 'visited': 2}Passed
regression door direction #1{'keys': ['blue', 'gold', 'red'], 'solvable': False, 'visited': 4}{'keys': ['blue', 'gold', 'red'], 'solvable': True, 'visited': 7}Failed
wrong colour #1{'keys': ['blue'], 'solvable': False, 'visited': 1}{'keys': ['blue'], 'solvable': False, 'visited': 1}Passed
control #1{'keys': [], 'solvable': False, 'visited': 1}{'keys': [], 'solvable': False, 'visited': 1}Passed

SHA-256 / f511f576d85531dbf342e6ffc70844c83d1157b94fa79b6e23b63c9955e7f7f6

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(rooms, edges, start, goal):
    have = set()
    seen = {start}
    changed = True
    while changed:
        changed = False
        for r in list(seen):
            for k in rooms.get(r, []):
                if k not in have:
                    have.add(k)
                    changed = True
        for a, b, lock in edges:
            for u, v in ((b, a),):
                if u in seen and v not in seen and (lock is None or lock in have):
                    seen.add(v)
                    changed = True
    return {'solvable': goal in seen, 'keys': sorted(have), 'visited': len(seen)}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = [[('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('fault site door direction #1',
   [{'r0': ['gold'], 'r2': ['blue']},
    [['r2', 'r1', 'gold'],
     ['r3', 'r1', 'blue'],
     ['r1', 'r3', None],
     ['r1', 'r0', None],
     ['r2', 'r3', 'blue']],
    'r0',
    'r3'],
   {'solvable': True, 'keys': ['blue', 'gold'], 'visited': 4}),
  ('fault site door direction #2',
   [{'r0': ['red'], 'r3': ['gold']},
    [['r4', 'r2', None], ['r0', 'r1', 'blue'], ['r2', 'r0', None], ['r2', 'r3', 'gold']],
    'r0',
    'r4'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('partial repair boundary #1',
   [{'r0': ['gold'], 'r1': ['red'], 'r2': ['gold']},
    [['r0', 'r1', 'red'], ['r2', 'r1', 'red'], ['r0', 'r2', None]],
    'r0',
    'r2'],
   {'solvable': True, 'keys': ['gold'], 'visited': 2}),
  ('regression door direction #1',
   [{'r0': ['red'], 'r1': ['gold'], 'r4': ['gold'], 'r5': ['blue'], 'r6': ['red']},
    [['r1', 'r2', 'blue'],
     ['r0', 'r2', 'red'],
     ['r0', 'r1', 'blue'],
     ['r3', 'r6', 'gold'],
     ['r4', 'r0', None],
     ['r3', 'r2', 'blue'],
     ['r2', 'r5', None]],
    'r0',
    'r6'],
   {'solvable': True, 'keys': ['blue', 'gold', 'red'], 'visited': 7}),
  ('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('control #1', [{}, [['r0', 'r1', 'blue']], 'r0', 'r1'], {'solvable': False, 'keys': [], 'visited': 1})],
 [('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('fault site door direction #1',
   [{'r0': ['red'], 'r3': ['gold']},
    [['r4', 'r2', None], ['r0', 'r1', 'blue'], ['r2', 'r0', None], ['r2', 'r3', 'gold']],
    'r0',
    'r4'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('fault site door direction #2',
   [{'r4': ['red']},
    [['r3', 'r1', 'gold'], ['r3', 'r4', 'blue'], ['r2', 'r1', None], ['r1', 'r0', None]],
    'r0',
    'r3'],
   {'solvable': False, 'keys': [], 'visited': 3}),
  ('regression door direction #1',
   [{'r0': ['red'], 'r1': ['gold'], 'r4': ['gold'], 'r5': ['blue'], 'r6': ['red']},
    [['r1', 'r2', 'blue'],
     ['r0', 'r2', 'red'],
     ['r0', 'r1', 'blue'],
     ['r3', 'r6', 'gold'],
     ['r4', 'r0', None],
     ['r3', 'r2', 'blue'],
     ['r2', 'r5', None]],
    'r0',
    'r6'],
   {'solvable': True, 'keys': ['blue', 'gold', 'red'], 'visited': 7}),
  ('partial repair boundary #1',
   [{'r0': ['red']}, [['r0', 'r1', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': ['red'], 'visited': 2}),
  ('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('control #1', [{}, [['r0', 'r1', 'blue']], 'r0', 'r1'], {'solvable': False, 'keys': [], 'visited': 1})],
 [('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('regression door direction #1',
   [{'r0': ['red'], 'r1': ['gold'], 'r4': ['gold'], 'r5': ['blue'], 'r6': ['red']},
    [['r1', 'r2', 'blue'],
     ['r0', 'r2', 'red'],
     ['r0', 'r1', 'blue'],
     ['r3', 'r6', 'gold'],
     ['r4', 'r0', None],
     ['r3', 'r2', 'blue'],
     ['r2', 'r5', None]],
    'r0',
    'r6'],
   {'solvable': True, 'keys': ['blue', 'gold', 'red'], 'visited': 7}),
  ('fault site door direction #1',
   [{'r3': ['blue'], 'r4': ['gold']},
    [['r4', 'r1', 'blue'],
     ['r5', 'r3', None],
     ['r5', 'r4', 'red'],
     ['r1', 'r0', 'gold'],
     ['r0', 'r2', 'blue'],
     ['r4', 'r0', None],
     ['r3', 'r2', None]],
    'r0',
    'r4'],
   {'solvable': True, 'keys': ['gold'], 'visited': 3}),
  ('regression door direction #2',
   [{'r0': ['blue'], 'r3': ['red']},
    [['r1', 'r0', None],
     ['r5', 'r3', None],
     ['r1', 'r2', 'red'],
     ['r3', 'r2', 'red'],
     ['r0', 'r4', 'gold'],
     ['r3', 'r1', None],
     ['r0', 'r5', 'gold']],
    'r0',
    'r5'],
   {'solvable': True, 'keys': ['blue', 'red'], 'visited': 5}),
  ('regression door direction #3',
   [{'r1': ['red']},
    [['r3', 'r2', 'gold'], ['r1', 'r3', 'red'], ['r1', 'r0', 'gold'], ['r2', 'r0', None], ['r1', 'r2', None]],
    'r0',
    'r3'],
   {'solvable': True, 'keys': ['red'], 'visited': 4}),
  ('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('control #1',
   [{'r1': ['red'], 'r2': ['gold']},
    [['r1', 'r2', 'blue'], ['r1', 'r0', 'red'], ['r4', 'r2', 'blue'], ['r1', 'r3', None]],
    'r0',
    'r2'],
   {'solvable': False, 'keys': [], 'visited': 1})],
 [('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('fault site door direction #1',
   [{'r0': ['blue'], 'r1': ['gold']},
    [['r0', 'r1', 'red'], ['r1', 'r0', 'blue'], ['r0', 'r1', 'red']],
    'r0',
    'r1'],
   {'solvable': True, 'keys': ['blue', 'gold'], 'visited': 2}),
  ('regression door direction #1',
   [{'r0': ['blue'], 'r3': ['red']},
    [['r1', 'r0', None],
     ['r5', 'r3', None],
     ['r1', 'r2', 'red'],
     ['r3', 'r2', 'red'],
     ['r0', 'r4', 'gold'],
     ['r3', 'r1', None],
     ['r0', 'r5', 'gold']],
    'r0',
    'r5'],
   {'solvable': True, 'keys': ['blue', 'red'], 'visited': 5}),
  ('partial repair boundary #1',
   [{'r3': ['red'], 'r5': ['red']},
    [['r1', 'r3', 'gold'],
     ['r2', 'r3', 'blue'],
     ['r2', 'r1', 'blue'],
     ['r0', 'r1', None],
     ['r2', 'r4', 'gold'],
     ['r5', 'r4', 'red']],
    'r0',
    'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('regression door direction #2',
   [{'r1': ['red'], 'r4': ['blue'], 'r6': ['gold']},
    [['r1', 'r0', 'blue'],
     ['r2', 'r6', 'blue'],
     ['r5', 'r4', None],
     ['r0', 'r2', 'gold'],
     ['r1', 'r3', None],
     ['r0', 'r4', None]],
    'r0',
    'r5'],
   {'solvable': True, 'keys': ['blue', 'red'], 'visited': 5}),
  ('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('control #1',
   [{'r2': ['red']},
    [['r1', 'r0', 'blue'], ['r1', 'r2', None], ['r1', 'r2', 'blue'], ['r1', 'r2', 'blue']],
    'r0',
    'r2'],
   {'solvable': False, 'keys': [], 'visited': 1})],
 [('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('regression door direction #1',
   [{'r1': ['red']},
    [['r3', 'r2', 'gold'], ['r1', 'r3', 'red'], ['r1', 'r0', 'gold'], ['r2', 'r0', None], ['r1', 'r2', None]],
    'r0',
    'r3'],
   {'solvable': True, 'keys': ['red'], 'visited': 4}),
  ('fault site door direction #1',
   [{'r4': ['blue']},
    [['r6', 'r1', None],
     ['r1', 'r0', None],
     ['r1', 'r5', 'blue'],
     ['r2', 'r1', 'gold'],
     ['r4', 'r0', 'blue'],
     ['r3', 'r6', None],
     ['r4', 'r5', None],
     ['r3', 'r1', 'gold']],
    'r0',
    'r2'],
   {'solvable': False, 'keys': [], 'visited': 4}),
  ('regression door direction #2',
   [{'r0': ['gold'], 'r2': ['gold'], 'r3': ['red'], 'r4': ['red']},
    [['r0', 'r1', None],
     ['r1', 'r2', 'blue'],
     ['r6', 'r1', None],
     ['r5', 'r0', 'blue'],
     ['r3', 'r2', 'gold'],
     ['r4', 'r0', None]],
    'r0',
    'r3'],
   {'solvable': False, 'keys': ['gold', 'red'], 'visited': 4}),
  ('partial repair boundary #1',
   [{'r0': ['red']}, [['r0', 'r1', 'red'], ['r0', 'r1', None], ['r1', 'r0', 'blue']], 'r0', 'r1'],
   {'solvable': True, 'keys': ['red'], 'visited': 2}),
  ('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('control #1',
   [{}, [['r1', 'r0', 'red'], ['r2', 'r1', None]], 'r0', 'r1'],
   {'solvable': False, 'keys': [], 'visited': 1})]]
for label, args, expected in cases[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
reverse listed door #1{'keys': [], 'solvable': True, 'visited': 2}{'keys': [], 'solvable': True, 'visited': 2}Passed
key behind first door #1{'keys': [], 'solvable': False, 'visited': 1}{'keys': ['red'], 'solvable': True, 'visited': 3}Failed
fault site door direction #1{'keys': ['blue', 'gold'], 'solvable': True, 'visited': 4}{'keys': ['blue', 'gold'], 'solvable': True, 'visited': 4}Passed
fault site door direction #2{'keys': ['red'], 'solvable': True, 'visited': 3}{'keys': ['red'], 'solvable': True, 'visited': 3}Passed
partial repair boundary #1{'keys': ['gold'], 'solvable': False, 'visited': 1}{'keys': ['gold'], 'solvable': True, 'visited': 2}Failed
regression door direction #1{'keys': ['gold', 'red'], 'solvable': False, 'visited': 2}{'keys': ['blue', 'gold', 'red'], 'solvable': True, 'visited': 7}Failed
wrong colour #1{'keys': ['blue'], 'solvable': False, 'visited': 1}{'keys': ['blue'], 'solvable': False, 'visited': 1}Passed
control #1{'keys': [], 'solvable': False, 'visited': 1}{'keys': [], 'solvable': False, 'visited': 1}Passed

SHA-256 / 20df8f03b97855f3559fbffc75fe0ef771865767df41cbd4783b309f66c65adf

3 / The verified repair

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

N = 1
observations = []
def solve(rooms, edges, start, goal):
    have = set()
    seen = {start}
    changed = True
    while changed:
        changed = False
        for r in list(seen):
            for k in rooms.get(r, []):
                if k not in have:
                    have.add(k)
                    changed = True
        for a, b, lock in edges:
            for u, v in ((a, b), (b, a)):
                if u in seen and v not in seen and (lock is None or lock in have):
                    seen.add(v)
                    changed = True
    return {'solvable': goal in seen, 'keys': sorted(have), 'visited': len(seen)}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = [[('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('fault site door direction #1',
   [{'r0': ['gold'], 'r2': ['blue']},
    [['r2', 'r1', 'gold'],
     ['r3', 'r1', 'blue'],
     ['r1', 'r3', None],
     ['r1', 'r0', None],
     ['r2', 'r3', 'blue']],
    'r0',
    'r3'],
   {'solvable': True, 'keys': ['blue', 'gold'], 'visited': 4}),
  ('fault site door direction #2',
   [{'r0': ['red'], 'r3': ['gold']},
    [['r4', 'r2', None], ['r0', 'r1', 'blue'], ['r2', 'r0', None], ['r2', 'r3', 'gold']],
    'r0',
    'r4'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('partial repair boundary #1',
   [{'r0': ['gold'], 'r1': ['red'], 'r2': ['gold']},
    [['r0', 'r1', 'red'], ['r2', 'r1', 'red'], ['r0', 'r2', None]],
    'r0',
    'r2'],
   {'solvable': True, 'keys': ['gold'], 'visited': 2}),
  ('regression door direction #1',
   [{'r0': ['red'], 'r1': ['gold'], 'r4': ['gold'], 'r5': ['blue'], 'r6': ['red']},
    [['r1', 'r2', 'blue'],
     ['r0', 'r2', 'red'],
     ['r0', 'r1', 'blue'],
     ['r3', 'r6', 'gold'],
     ['r4', 'r0', None],
     ['r3', 'r2', 'blue'],
     ['r2', 'r5', None]],
    'r0',
    'r6'],
   {'solvable': True, 'keys': ['blue', 'gold', 'red'], 'visited': 7}),
  ('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('control #1', [{}, [['r0', 'r1', 'blue']], 'r0', 'r1'], {'solvable': False, 'keys': [], 'visited': 1})],
 [('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('fault site door direction #1',
   [{'r0': ['red'], 'r3': ['gold']},
    [['r4', 'r2', None], ['r0', 'r1', 'blue'], ['r2', 'r0', None], ['r2', 'r3', 'gold']],
    'r0',
    'r4'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('fault site door direction #2',
   [{'r4': ['red']},
    [['r3', 'r1', 'gold'], ['r3', 'r4', 'blue'], ['r2', 'r1', None], ['r1', 'r0', None]],
    'r0',
    'r3'],
   {'solvable': False, 'keys': [], 'visited': 3}),
  ('regression door direction #1',
   [{'r0': ['red'], 'r1': ['gold'], 'r4': ['gold'], 'r5': ['blue'], 'r6': ['red']},
    [['r1', 'r2', 'blue'],
     ['r0', 'r2', 'red'],
     ['r0', 'r1', 'blue'],
     ['r3', 'r6', 'gold'],
     ['r4', 'r0', None],
     ['r3', 'r2', 'blue'],
     ['r2', 'r5', None]],
    'r0',
    'r6'],
   {'solvable': True, 'keys': ['blue', 'gold', 'red'], 'visited': 7}),
  ('partial repair boundary #1',
   [{'r0': ['red']}, [['r0', 'r1', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': ['red'], 'visited': 2}),
  ('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('control #1', [{}, [['r0', 'r1', 'blue']], 'r0', 'r1'], {'solvable': False, 'keys': [], 'visited': 1})],
 [('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('regression door direction #1',
   [{'r0': ['red'], 'r1': ['gold'], 'r4': ['gold'], 'r5': ['blue'], 'r6': ['red']},
    [['r1', 'r2', 'blue'],
     ['r0', 'r2', 'red'],
     ['r0', 'r1', 'blue'],
     ['r3', 'r6', 'gold'],
     ['r4', 'r0', None],
     ['r3', 'r2', 'blue'],
     ['r2', 'r5', None]],
    'r0',
    'r6'],
   {'solvable': True, 'keys': ['blue', 'gold', 'red'], 'visited': 7}),
  ('fault site door direction #1',
   [{'r3': ['blue'], 'r4': ['gold']},
    [['r4', 'r1', 'blue'],
     ['r5', 'r3', None],
     ['r5', 'r4', 'red'],
     ['r1', 'r0', 'gold'],
     ['r0', 'r2', 'blue'],
     ['r4', 'r0', None],
     ['r3', 'r2', None]],
    'r0',
    'r4'],
   {'solvable': True, 'keys': ['gold'], 'visited': 3}),
  ('regression door direction #2',
   [{'r0': ['blue'], 'r3': ['red']},
    [['r1', 'r0', None],
     ['r5', 'r3', None],
     ['r1', 'r2', 'red'],
     ['r3', 'r2', 'red'],
     ['r0', 'r4', 'gold'],
     ['r3', 'r1', None],
     ['r0', 'r5', 'gold']],
    'r0',
    'r5'],
   {'solvable': True, 'keys': ['blue', 'red'], 'visited': 5}),
  ('regression door direction #3',
   [{'r1': ['red']},
    [['r3', 'r2', 'gold'], ['r1', 'r3', 'red'], ['r1', 'r0', 'gold'], ['r2', 'r0', None], ['r1', 'r2', None]],
    'r0',
    'r3'],
   {'solvable': True, 'keys': ['red'], 'visited': 4}),
  ('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('control #1',
   [{'r1': ['red'], 'r2': ['gold']},
    [['r1', 'r2', 'blue'], ['r1', 'r0', 'red'], ['r4', 'r2', 'blue'], ['r1', 'r3', None]],
    'r0',
    'r2'],
   {'solvable': False, 'keys': [], 'visited': 1})],
 [('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('fault site door direction #1',
   [{'r0': ['blue'], 'r1': ['gold']},
    [['r0', 'r1', 'red'], ['r1', 'r0', 'blue'], ['r0', 'r1', 'red']],
    'r0',
    'r1'],
   {'solvable': True, 'keys': ['blue', 'gold'], 'visited': 2}),
  ('regression door direction #1',
   [{'r0': ['blue'], 'r3': ['red']},
    [['r1', 'r0', None],
     ['r5', 'r3', None],
     ['r1', 'r2', 'red'],
     ['r3', 'r2', 'red'],
     ['r0', 'r4', 'gold'],
     ['r3', 'r1', None],
     ['r0', 'r5', 'gold']],
    'r0',
    'r5'],
   {'solvable': True, 'keys': ['blue', 'red'], 'visited': 5}),
  ('partial repair boundary #1',
   [{'r3': ['red'], 'r5': ['red']},
    [['r1', 'r3', 'gold'],
     ['r2', 'r3', 'blue'],
     ['r2', 'r1', 'blue'],
     ['r0', 'r1', None],
     ['r2', 'r4', 'gold'],
     ['r5', 'r4', 'red']],
    'r0',
    'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('regression door direction #2',
   [{'r1': ['red'], 'r4': ['blue'], 'r6': ['gold']},
    [['r1', 'r0', 'blue'],
     ['r2', 'r6', 'blue'],
     ['r5', 'r4', None],
     ['r0', 'r2', 'gold'],
     ['r1', 'r3', None],
     ['r0', 'r4', None]],
    'r0',
    'r5'],
   {'solvable': True, 'keys': ['blue', 'red'], 'visited': 5}),
  ('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('control #1',
   [{'r2': ['red']},
    [['r1', 'r0', 'blue'], ['r1', 'r2', None], ['r1', 'r2', 'blue'], ['r1', 'r2', 'blue']],
    'r0',
    'r2'],
   {'solvable': False, 'keys': [], 'visited': 1})],
 [('reverse listed door #1',
   [{}, [['r1', 'r0', None]], 'r0', 'r1'],
   {'solvable': True, 'keys': [], 'visited': 2}),
  ('key behind first door #1',
   [{'r1': ['red']}, [['r1', 'r2', 'red'], ['r0', 'r1', None]], 'r0', 'r2'],
   {'solvable': True, 'keys': ['red'], 'visited': 3}),
  ('regression door direction #1',
   [{'r1': ['red']},
    [['r3', 'r2', 'gold'], ['r1', 'r3', 'red'], ['r1', 'r0', 'gold'], ['r2', 'r0', None], ['r1', 'r2', None]],
    'r0',
    'r3'],
   {'solvable': True, 'keys': ['red'], 'visited': 4}),
  ('fault site door direction #1',
   [{'r4': ['blue']},
    [['r6', 'r1', None],
     ['r1', 'r0', None],
     ['r1', 'r5', 'blue'],
     ['r2', 'r1', 'gold'],
     ['r4', 'r0', 'blue'],
     ['r3', 'r6', None],
     ['r4', 'r5', None],
     ['r3', 'r1', 'gold']],
    'r0',
    'r2'],
   {'solvable': False, 'keys': [], 'visited': 4}),
  ('regression door direction #2',
   [{'r0': ['gold'], 'r2': ['gold'], 'r3': ['red'], 'r4': ['red']},
    [['r0', 'r1', None],
     ['r1', 'r2', 'blue'],
     ['r6', 'r1', None],
     ['r5', 'r0', 'blue'],
     ['r3', 'r2', 'gold'],
     ['r4', 'r0', None]],
    'r0',
    'r3'],
   {'solvable': False, 'keys': ['gold', 'red'], 'visited': 4}),
  ('partial repair boundary #1',
   [{'r0': ['red']}, [['r0', 'r1', 'red'], ['r0', 'r1', None], ['r1', 'r0', 'blue']], 'r0', 'r1'],
   {'solvable': True, 'keys': ['red'], 'visited': 2}),
  ('wrong colour #1',
   [{'r0': ['blue']}, [['r0', 'r1', 'red']], 'r0', 'r1'],
   {'solvable': False, 'keys': ['blue'], 'visited': 1}),
  ('control #1',
   [{}, [['r1', 'r0', 'red'], ['r2', 'r1', None]], 'r0', 'r1'],
   {'solvable': False, 'keys': [], 'visited': 1})]]
for label, args, expected in cases[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
reverse listed door #1{'keys': [], 'solvable': True, 'visited': 2}{'keys': [], 'solvable': True, 'visited': 2}Passed
key behind first door #1{'keys': ['red'], 'solvable': True, 'visited': 3}{'keys': ['red'], 'solvable': True, 'visited': 3}Passed
fault site door direction #1{'keys': ['blue', 'gold'], 'solvable': True, 'visited': 4}{'keys': ['blue', 'gold'], 'solvable': True, 'visited': 4}Passed
fault site door direction #2{'keys': ['red'], 'solvable': True, 'visited': 3}{'keys': ['red'], 'solvable': True, 'visited': 3}Passed
partial repair boundary #1{'keys': ['gold'], 'solvable': True, 'visited': 2}{'keys': ['gold'], 'solvable': True, 'visited': 2}Passed
regression door direction #1{'keys': ['blue', 'gold', 'red'], 'solvable': True, 'visited': 7}{'keys': ['blue', 'gold', 'red'], 'solvable': True, 'visited': 7}Passed
wrong colour #1{'keys': ['blue'], 'solvable': False, 'visited': 1}{'keys': ['blue'], 'solvable': False, 'visited': 1}Passed
control #1{'keys': [], 'solvable': False, 'visited': 1}{'keys': [], 'solvable': False, 'visited': 1}Passed

SHA-256 / 65839cbb7fe4cab5e089f0b7dc8ff0e7b34f16b42fcc8154dee1cb71b8292c41

Verification & scope

Deterministic toy contract stipulated for this model; integer or exact arithmetic only, not a reproduction of any specific game engine. 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 2026-09-29T14:50:49.285514+00:00.

Case digest / b37c7d998892ba9936efed4f13f79e997d850122764e18b2cb7a44f040f51824