{"abstract":"Treasure spawns on doors or over chasms.","category":"Procedural level generation constraints","checks":8,"contract":"Cells: '#' wall, '~' chasm (not walkable), '.' floor, 'D' door (walkable). A dead end is a '.' cell, other than start and exit ([row, col] lists), with exactly one walkable in-bounds 4-neighbour. Returns dead ends in row-major order.","contract_signature":"grid, start, exit","evaluation_group":"w2-procedural-level-generation-constraints-dead-ends","failed_approach":"Still admits doors as treasure cells.","family":"w2-procedural-level-generation-constraints-dead-ends-candidate-tile","id":"FA-86601","implementations":{"attempt":{"sha256":"c8bef56f614eade5e2c51799ab0214f748245a1152a2c1b53251e5284f2ba00e","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(grid, start, exit):\n    h = len(grid)\n    w = len(grid[0])\n    ends = []\n    for r in range(h):\n        for c in range(w):\n            if grid[r][c] not in '.D' or [r, c] in (start, exit):\n                continue\n            n = 0\n            for dr, dc in ((1, 0), (-1, 0), (0, 1), (0, -1)):\n                rr, cc = r + dr, c + dc\n                if 0 <= rr < h and 0 <= cc < w and grid[rr][cc] in '.D':\n                    n += 1\n            if n == 1:\n                ends.append([r, c])\n    return ends\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncases = [[('regression candidate tile #1', [['...D#~', '~.###~', '~..D..'], [1, 3], [0, 2]], [[0, 0], [2, 5]]),\n  ('regression candidate tile #2',\n   [['#~.#.', '#...D', 'D.#..', '#....', '##..~'], [3, 0], [3, 3]],\n   [[0, 2], [0, 4]]),\n  ('regression candidate tile #3', [['~D.#D', '#.#~.'], [0, 1], [1, 2]], [[0, 2], [1, 1], [1, 4]]),\n  ('regression candidate tile #4', [['.~~##.', '##~DD~'], [0, 1], [1, 0]], []),\n  ('door as neighbour #1', [['#D#', '#.#', '###'], [0, 1], [0, 1]], [[1, 1]]),\n  ('chasm edge #1', [['.~.', '...'], [1, 1], [1, 1]], [[0, 0], [0, 2]]),\n  ('isolated floor #1', [['#.#', '###'], [1, 0], [1, 0]], []),\n  ('control #1', [['#.#.#', '.#D~~', '..~..', '..D.~'], [1, 4], [2, 0]], [[1, 0], [2, 4]])],\n [('regression candidate tile #1', [['~D.#D', '#.#~.'], [0, 1], [1, 2]], [[0, 2], [1, 1], [1, 4]]),\n  ('regression candidate tile #2', [['.~~##.', '##~DD~'], [0, 1], [1, 0]], []),\n  ('regression candidate tile #3', [['##.#.', '.~#D.', 'D#.~#'], [0, 3], [1, 4]], [[0, 4], [1, 0]]),\n  ('regression candidate tile #4',\n   [['.###..', '~#~~..', '....~.', '~D~...', '.#~D~.', '~D...#'], [3, 0], [1, 0]],\n   [[2, 0], [4, 5], [5, 4]]),\n  ('isolated floor #1', [['#.#', '###'], [1, 0], [1, 0]], []),\n  ('door as neighbour #1', [['#D#', '#.#', '###'], [0, 1], [0, 1]], [[1, 1]]),\n  ('control #1', [['#.#.#', '.#D~~', '..~..', '..D.~'], [1, 4], [2, 0]], [[1, 0], [2, 4]]),\n  ('control #2', [['D.', 'DD', '.~', '#.'], [3, 0], [3, 0]], [[2, 0]])],\n [('fault site candidate tile #1', [['...#~.', 'D.~~.D'], [1, 1], [1, 1]], [[0, 2], [0, 5], [1, 4]]),\n  ('fault site candidate tile #2',\n   [['..#...', '~..##.', '##~##.'], [0, 0], [0, 5]],\n   [[0, 3], [1, 2], [2, 5]]),\n  ('regression candidate tile #1', [['##.#.', '.~#D.', 'D#.~#'], [0, 3], [1, 4]], [[0, 4], [1, 0]]),\n  ('regression candidate tile #2',\n   [['.###..', '~#~~..', '....~.', '~D~...', '.#~D~.', '~D...#'], [3, 0], [1, 0]],\n   [[2, 0], [4, 5], [5, 4]]),\n  ('chasm edge #1', [['.~.', '...'], [1, 1], [1, 1]], [[0, 0], [0, 2]]),\n  ('isolated floor #1', [['#.#', '###'], [1, 0], [1, 0]], []),\n  ('control #1', [['D.', 'DD', '.~', '#.'], [3, 0], [3, 0]], [[2, 0]]),\n  ('control #2', [['.##', '#..'], [1, 2], [0, 1]], [[1, 1]])],\n [('fault site candidate tile #1', [['~.##.', 'D..#~', '...##'], [0, 3], [0, 1]], []),\n  ('regression candidate tile #1', [['##.#.', '.~#D.', 'D#.~#'], [0, 3], [1, 4]], [[0, 4], [1, 0]]),\n  ('regression candidate tile #2',\n   [['..###', '..~#.', '#...D', '..##D', '.#.#D'], [4, 2], [0, 4]],\n   [[1, 4], [4, 0]]),\n  ('regression candidate tile #3',\n   [['.~.#', '...#', '.#.D', '#~D~', '#~..'], [0, 1], [1, 2]],\n   [[0, 0], [0, 2], [2, 0], [4, 3]]),\n  ('door as neighbour #1', [['#D#', '#.#', '###'], [0, 1], [0, 1]], [[1, 1]]),\n  ('chasm edge #1', [['.~.', '...'], [1, 1], [1, 1]], [[0, 0], [0, 2]]),\n  ('control #1', [['.#', '..', '~~', 'D.', 'D.'], [3, 0], [2, 0]], [[0, 0], [1, 1]]),\n  ('control #2', [['DD', '~.', '#.', 'D~'], [3, 0], [0, 0]], [[2, 1]])],\n [('fault site candidate tile #1',\n   [['.D~~.~', '~..#.D', '#~D.#.', '#..~.#', '.#...#'], [1, 5], [0, 5]],\n   [[0, 0], [0, 4], [2, 3], [2, 5], [3, 1], [3, 4]]),\n  ('fault site candidate tile #2', [['~#~', '..#'], [1, 2], [0, 2]], [[1, 0], [1, 1]]),\n  ('regression candidate tile #1',\n   [['#D...D', '#D#...', '##.##.', '#.##.#', '#D##.~', 'D.#...'], [2, 5], [5, 3]],\n   [[3, 1], [3, 4], [5, 5]]),\n  ('regression candidate tile #2', [['.D#.D', 'D...#', '~.~.D', '.D#.#'], [1, 2], [3, 4]], [[3, 0], [3, 3]]),\n  ('isolated floor #1', [['#.#', '###'], [1, 0], [1, 0]], []),\n  ('door as neighbour #1', [['#D#', '#.#', '###'], [0, 1], [0, 1]], [[1, 1]]),\n  ('control #1', [['DDD.', '...#'], [1, 2], [0, 1]], [[0, 3]]),\n  ('control #2', [['.#...~', '.#.D~D', '....##'], [1, 0], [0, 0]], [[0, 4]])]]\nfor label, args, expected in cases[N-1]:\n    check(label, solve(*args), expected)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"broken":{"sha256":"ab3dc389a49a5b4a07394131f712f0ee4bd7295b3decbe8a06e0eac92dfab48d","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\n\nN = 1\nobservations = []\ndef solve(grid, start, exit):\n    h = len(grid)\n    w = len(grid[0])\n    ends = []\n    for r in range(h):\n        for c in range(w):\n            if grid[r][c] == '#' or [r, c] in (start, exit):\n                continue\n            n = 0\n            for dr, dc in ((1, 0), (-1, 0), (0, 1), (0, -1)):\n                rr, cc = r + dr, c + dc\n                if 0 <= rr < h and 0 <= cc < w and grid[rr][cc] in '.D':\n                    n += 1\n            if n == 1:\n                ends.append([r, c])\n    return ends\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\ncases = [[('regression candidate tile #1', [['...D#~', '~.###~', '~..D..'], [1, 3], [0, 2]], [[0, 0], [2, 5]]),\n  ('regression candidate tile #2',\n   [['#~.#.', '#...D', 'D.#..', '#....', '##..~'], [3, 0], [3, 3]],\n   [[0, 2], [0, 4]]),\n  ('regression candidate tile #3', [['~D.#D', '#.#~.'], [0, 1], [1, 2]], [[0, 2], [1, 1], [1, 4]]),\n  ('regression candidate tile #4', [['.~~##.', '##~DD~'], [0, 1], [1, 0]], []),\n  ('door as neighbour #1', [['#D#', '#.#', '###'], [0, 1], [0, 1]], [[1, 1]]),\n  ('chasm edge #1', [['.~.', '...'], [1, 1], [1, 1]], [[0, 0], [0, 2]]),\n  ('isolated floor #1', [['#.#', '###'], [1, 0], [1, 0]], []),\n  ('control #1', [['#.#.#', '.#D~~', '..~..', '..D.~'], [1, 4], [2, 0]], [[1, 0], [2, 4]])],\n [('regression candidate tile #1', [['~D.#D', '#.#~.'], [0, 1], [1, 2]], [[0, 2], [1, 1], [1, 4]]),\n  ('regression candidate tile #2', [['.~~##.', '##~DD~'], [0, 1], [1, 0]], []),\n  ('regression candidate tile #3', [['##.#.', '.~#D.', 'D#.~#'], [0, 3], [1, 4]], [[0, 4], [1, 0]]),\n  ('regression candidate tile #4',\n   [['.###..', '~#~~..', '....~.', '~D~...', '.#~D~.', '~D...#'], [3, 0], [1, 0]],\n   [[2, 0], [4, 5], [5, 4]]),\n  ('isolated floor #1', [['#.#', '###'], [1, 0], [1, 0]], []),\n  ('door as neighbour #1', [['#D#', '#.#', '###'], [0, 1], [0, 1]], [[1, 1]]),\n  ('control #1', [['#.#.#', '.#D~~', '..~..', '..D.~'], [1, 4], [2, 0]], [[1, 0], [2, 4]]),\n  ('control #2', [['D.', 'DD', '.~', '#.'], [3, 0], [3, 0]], [[2, 0]])],\n [('fault site candidate tile #1', [['...#~.', 'D.~~.D'], [1, 1], [1, 1]], [[0, 2], [0, 5], [1, 4]]),\n  ('fault site candidate tile #2',\n   [['..#...', '~..##.', '##~##.'], [0, 0], [0, 5]],\n   [[0, 3], [1, 2], [2, 5]]),\n  ('regression candidate tile #1', [['##.#.', '.~#D.', 'D#.~#'], [0, 3], [1, 4]], [[0, 4], [1, 0]]),\n  ('regression candidate tile #2',\n   [['.###..', '~#~~..', '....~.', '~D~...', '.#~D~.', '~D...#'], [3, 0], [1, 0]],\n   [[2, 0], [4, 5], [5, 4]]),\n  ('chasm edge #1', [['.~.', '...'], [1, 1], [1, 1]], [[0, 0], [0, 2]]),\n  ('isolated floor #1', [['#.#', '###'], [1, 0], [1, 0]], []),\n  ('control #1', [['D.', 'DD', '.~', '#.'], [3, 0], [3, 0]], [[2, 0]]),\n  ('control #2', [['.##', '#..'], [1, 2], [0, 1]], [[1, 1]])],\n [('fault site candidate tile #1', [['~.##.', 'D..#~', '...##'], [0, 3], [0, 1]], []),\n  ('regression candidate tile #1', [['##.#.', '.~#D.', 'D#.~#'], [0, 3], [1, 4]], [[0, 4], [1, 0]]),\n  ('regression candidate tile #2',\n   [['..###', '..~#.', '#...D', '..##D', '.#.#D'], [4, 2], [0, 4]],\n   [[1, 4], [4, 0]]),\n  ('regression candidate tile #3',\n   [['.~.#', '...#', '.#.D', '#~D~', '#~..'], [0, 1], [1, 2]],\n   [[0, 0], [0, 2], [2, 0], [4, 3]]),\n  ('door as neighbour #1', [['#D#', '#.#', '###'], [0, 1], [0, 1]], [[1, 1]]),\n  ('chasm edge #1', [['.~.', '...'], [1, 1], [1, 1]], [[0, 0], [0, 2]]),\n  ('control #1', [['.#', '..', '~~', 'D.', 'D.'], [3, 0], [2, 0]], [[0, 0], [1, 1]]),\n  ('control #2', [['DD', '~.', '#.', 'D~'], [3, 0], [0, 0]], [[2, 1]])],\n [('fault site candidate tile #1',\n   [['.D~~.~', '~..#.D', '#~D.#.', '#..~.#', '.#...#'], [1, 5], [0, 5]],\n   [[0, 0], [0, 4], [2, 3], [2, 5], [3, 1], [3, 4]]),\n  ('fault site candidate tile #2', [['~#~', '..#'], [1, 2], [0, 2]], [[1, 0], [1, 1]]),\n  ('regression candidate tile #1',\n   [['#D...D', '#D#...', '##.##.', '#.##.#', '#D##.~', 'D.#...'], [2, 5], [5, 3]],\n   [[3, 1], [3, 4], [5, 5]]),\n  ('regression candidate tile #2', [['.D#.D', 'D...#', '~.~.D', '.D#.#'], [1, 2], [3, 4]], [[3, 0], [3, 3]]),\n  ('isolated floor #1', [['#.#', '###'], [1, 0], [1, 0]], []),\n  ('door as neighbour #1', [['#D#', '#.#', '###'], [0, 1], [0, 1]], [[1, 1]]),\n  ('control #1', [['DDD.', '...#'], [1, 2], [0, 1]], [[0, 3]]),\n  ('control #2', [['.#...~', '.#.D~D', '....##'], [1, 0], [0, 0]], [[0, 4]])]]\nfor label, args, expected in cases[N-1]:\n    check(label, solve(*args), expected)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"}},"limitations":"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.","method":"Deterministic executable model with adversarial boundary fixtures.","provenance":{"created_by":"Failure Map","dependencies":"Python standard library","family":"w2-procedural-level-generation-constraints-dead-ends-candidate-tile","generated_at":"2026-09-29T14:50:51.126716+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"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.","root_cause":"Only walls are excluded as candidates.","sha256":"69aa5c1327bc7ccb054f9d5a4de6a50ba8d84c6c5602145a7af507db22ba2a41","title":"Treasure dead-end finder: Doors and chasms become treasure spots · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":40.911,"exit_code":1,"observations":[{"actual":[[0,0],[0,3],[2,5]],"check":"regression candidate tile #1","expected":[[0,0],[2,5]],"passed":false},{"actual":[[0,2],[0,4],[2,0]],"check":"regression candidate tile #2","expected":[[0,2],[0,4]],"passed":false},{"actual":[[0,2],[0,4],[1,1],[1,4]],"check":"regression candidate tile #3","expected":[[0,2],[1,1],[1,4]],"passed":false},{"actual":[[1,3],[1,4]],"check":"regression candidate tile #4","expected":[],"passed":false},{"actual":[[1,1]],"check":"door as neighbour #1","expected":[[1,1]],"passed":true},{"actual":[[0,0],[0,2]],"check":"chasm edge #1","expected":[[0,0],[0,2]],"passed":true},{"actual":[],"check":"isolated floor #1","expected":[],"passed":true},{"actual":[[1,0],[2,4]],"check":"control #1","expected":[[1,0],[2,4]],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"regression candidate tile #1\", \"actual\": [[0, 0], [0, 3], [2, 5]], \"expected\": [[0, 0], [2, 5]], \"passed\": false}, {\"check\": \"regression candidate tile #2\", \"actual\": [[0, 2], [0, 4], [2, 0]], \"expected\": [[0, 2], [0, 4]], \"passed\": false}, {\"check\": \"regression candidate tile #3\", \"actual\": [[0, 2], [0, 4], [1, 1], [1, 4]], \"expected\": [[0, 2], [1, 1], [1, 4]], \"passed\": false}, {\"check\": \"regression candidate tile #4\", \"actual\": [[1, 3], [1, 4]], \"expected\": [], \"passed\": false}, {\"check\": \"door as neighbour #1\", \"actual\": [[1, 1]], \"expected\": [[1, 1]], \"passed\": true}, {\"check\": \"chasm edge #1\", \"actual\": [[0, 0], [0, 2]], \"expected\": [[0, 0], [0, 2]], \"passed\": true}, {\"check\": \"isolated floor #1\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"control #1\", \"actual\": [[1, 0], [2, 4]], \"expected\": [[1, 0], [2, 4]], \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":39.047,"exit_code":1,"observations":[{"actual":[[0,0],[0,3],[1,5],[2,0],[2,5]],"check":"regression candidate tile #1","expected":[[0,0],[2,5]],"passed":false},{"actual":[[0,2],[0,4],[2,0]],"check":"regression candidate tile #2","expected":[[0,2],[0,4]],"passed":false},{"actual":[[0,0],[0,2],[0,4],[1,1],[1,3],[1,4]],"check":"regression candidate tile #3","expected":[[0,2],[1,1],[1,4]],"passed":false},{"actual":[[1,2],[1,3],[1,4]],"check":"regression candidate tile #4","expected":[],"passed":false},{"actual":[[1,1]],"check":"door as neighbour #1","expected":[[1,1]],"passed":true},{"actual":[[0,0],[0,2]],"check":"chasm edge #1","expected":[[0,0],[0,2]],"passed":true},{"actual":[],"check":"isolated floor #1","expected":[],"passed":true},{"actual":[[1,0],[2,4]],"check":"control #1","expected":[[1,0],[2,4]],"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"regression candidate tile #1\", \"actual\": [[0, 0], [0, 3], [1, 5], [2, 0], [2, 5]], \"expected\": [[0, 0], [2, 5]], \"passed\": false}, {\"check\": \"regression candidate tile #2\", \"actual\": [[0, 2], [0, 4], [2, 0]], \"expected\": [[0, 2], [0, 4]], \"passed\": false}, {\"check\": \"regression candidate tile #3\", \"actual\": [[0, 0], [0, 2], [0, 4], [1, 1], [1, 3], [1, 4]], \"expected\": [[0, 2], [1, 1], [1, 4]], \"passed\": false}, {\"check\": \"regression candidate tile #4\", \"actual\": [[1, 2], [1, 3], [1, 4]], \"expected\": [], \"passed\": false}, {\"check\": \"door as neighbour #1\", \"actual\": [[1, 1]], \"expected\": [[1, 1]], \"passed\": true}, {\"check\": \"chasm edge #1\", \"actual\": [[0, 0], [0, 2]], \"expected\": [[0, 0], [0, 2]], \"passed\": true}, {\"check\": \"isolated floor #1\", \"actual\": [], \"expected\": [], \"passed\": true}, {\"check\": \"control #1\", \"actual\": [[1, 0], [2, 4]], \"expected\": [[1, 0], [2, 4]], \"passed\": true}], \"passed\": false}\n"}},"member_only":{"stages":["fixed"],"fields":["implementations.fixed","verification.fixed","harness","repair"],"note":"The verified repair, its recorded checks, the repair description, and the scoring harness are available to members."}}