FAILURE MAP
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FA-86351 / Procedural level generation constraints / Open access

Room placement with padding: Rooms start on the border row · case 01

Rooms at column or row zero erase the top or left wall.

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

ROOT CAUSE

The near-side bound allows coordinate zero, which is the border.

VERIFIED REPAIR

Restore `x < 1 or y < 1` at the near border step.

Unsuccessful approach: Checking only x still lets rooms start on the top border row.

Case contract

Candidates [x, y, w, h] are tried in order. A room needs w >= 3 and h >= 3, must stay inside a one-tile border (x >= 1, y >= 1, x+w <= width-1, y+h <= height-1) and must keep at least pad empty tiles to every accepted room on both axes (rooms conflict when their pad-expanded extents overlap). Returns indices of accepted candidates.

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(width, height, candidates, pad):
    placed = []
    out = []
    for i, (x, y, w, h) in enumerate(candidates):
        if w < 3 or h < 3:
            continue
        if x < 0 or y < 0 or x + w > width - 1 or y + h > height - 1:
            continue
        ok = True
        for px, py, pw, ph in placed:
            if x < px + pw + pad and px < x + w + pad and y < py + ph + pad and py < y + h + pad:
                ok = False
                break
        if ok:
            placed.append((x, y, w, h))
            out.append(i)
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = [[('fault site near border #1',
   [13,
    21,
    [[9, 8, 5, 3], [11, 14, 8, 3], [7, 15, 3, 2], [-1, 10, 8, 6], [0, 3, 3, 3], [10, 0, 5, 6], [8, 13, 2, 4]],
    2],
   []),
  ('regression near border #1',
   [16,
    30,
    [[12, 13, 3, 6],
     [11, 9, 5, 3],
     [1, 0, 5, 3],
     [14, 10, 8, 3],
     [13, 19, 8, 4],
     [6, 14, 5, 6],
     [8, 18, 5, 2]],
    1],
   [0, 5]),
  ('partial repair boundary #1',
   [30, 11, [[-1, 1, 2, 2], [24, -1, 5, 3], [16, 4, 5, 6], [3, 1, 2, 6], [26, 2, 2, 3], [5, 9, 8, 2]], 0],
   [2]),
  ('partial repair boundary #2',
   [27,
    21,
    [[17, 14, 4, 3],
     [16, 17, 4, 3],
     [23, -1, 5, 3],
     [21, -1, 4, 4],
     [19, 6, 8, 6],
     [7, 11, 3, 3],
     [3, 2, 5, 2],
     [4, -1, 5, 3]],
    0],
   [0, 1, 5]),
  ('touching border tile #1', [10, 10, [[1, 1, 8, 8]], 1], [0]),
  ('rooms exactly pad apart #1', [20, 10, [[1, 1, 4, 4], [6, 1, 4, 4]], 1], [0, 1]),
  ('thin corridor room #1', [20, 20, [[2, 2, 2, 9], [2, 2, 5, 5]], 0], [1]),
  ('control #1',
   [25,
    23,
    [[5, 9, 3, 6],
     [8, 10, 5, 6],
     [9, 14, 5, 4],
     [-1, 1, 3, 6],
     [-1, 14, 2, 3],
     [17, 18, 4, 2],
     [4, 20, 3, 4]],
    1],
   [0, 2])],
 [('fault site near border #1', [8, 25, [[0, 8, 3, 6], [4, -1, 4, 3], [1, 17, 5, 2]], 1], []),
  ('fault site near border #2',
   [14,
    21,
    [[7, 6, 3, 6], [11, -1, 8, 2], [0, 12, 3, 3], [-1, 14, 8, 6], [6, 9, 3, 4], [1, 10, 4, 4], [9, 19, 2, 2]],
    0],
   [0, 5]),
  ('partial repair boundary #1',
   [26, 13, [[7, 10, 8, 4], [22, -1, 3, 6], [3, 3, 4, 6], [17, 0, 8, 2]], 1],
   [2]),
  ('regression near border #1',
   [16,
    30,
    [[12, 13, 3, 6],
     [11, 9, 5, 3],
     [1, 0, 5, 3],
     [14, 10, 8, 3],
     [13, 19, 8, 4],
     [6, 14, 5, 6],
     [8, 18, 5, 2]],
    1],
   [0, 5]),
  ('thin corridor room #1', [20, 20, [[2, 2, 2, 9], [2, 2, 5, 5]], 0], [1]),
  ('touching border tile #1', [10, 10, [[1, 1, 8, 8]], 1], [0]),
  ('control #1',
   [25,
    23,
    [[5, 9, 3, 6],
     [8, 10, 5, 6],
     [9, 14, 5, 4],
     [-1, 1, 3, 6],
     [-1, 14, 2, 3],
     [17, 18, 4, 2],
     [4, 20, 3, 4]],
    1],
   [0, 2]),
  ('control #2',
   [19, 27, [[6, 2, 3, 2], [4, 23, 5, 4], [4, 20, 2, 3], [12, 4, 8, 2], [10, 14, 8, 6]], 1],
   [4])],
 [('fault site near border #1',
   [16,
    29,
    [[4, 0, 2, 3], [10, 16, 4, 6], [5, 21, 3, 6], [1, 9, 3, 3], [0, 22, 4, 3], [-1, 21, 4, 6], [14, 4, 5, 2]],
    1],
   [1, 2, 3]),
  ('fault site near border #2',
   [29, 27, [[19, 5, 8, 3], [3, 14, 5, 3], [0, 20, 4, 4], [-1, 5, 3, 4], [0, 7, 5, 2]], 0],
   [0, 1]),
  ('partial repair boundary #1',
   [10, 8, [[7, 3, 3, 3], [2, 3, 5, 3], [5, 6, 5, 6], [6, 3, 3, 6], [8, 3, 2, 3], [2, -1, 4, 4]], 0],
   [1]),
  ('regression near border #1',
   [18,
    19,
    [[7, 11, 4, 2],
     [2, 8, 8, 2],
     [14, 9, 3, 3],
     [8, 8, 5, 2],
     [7, 13, 3, 2],
     [10, 12, 8, 2],
     [14, 5, 8, 4],
     [5, 0, 5, 4]],
    1],
   [2]),
  ('rooms exactly pad apart #1', [20, 10, [[1, 1, 4, 4], [6, 1, 4, 4]], 1], [0, 1]),
  ('thin corridor room #1', [20, 20, [[2, 2, 2, 9], [2, 2, 5, 5]], 0], [1]),
  ('control #1',
   [19, 27, [[6, 2, 3, 2], [4, 23, 5, 4], [4, 20, 2, 3], [12, 4, 8, 2], [10, 14, 8, 6]], 1],
   [4]),
  ('control #2', [15, 13, [[6, 11, 5, 6], [-1, 3, 2, 4]], 1], [])],
 [('regression near border #1',
   [18,
    19,
    [[7, 11, 4, 2],
     [2, 8, 8, 2],
     [14, 9, 3, 3],
     [8, 8, 5, 2],
     [7, 13, 3, 2],
     [10, 12, 8, 2],
     [14, 5, 8, 4],
     [5, 0, 5, 4]],
    1],
   [2]),
  ('regression near border #2',
   [19,
    18,
    [[15, 0, 4, 3], [6, 4, 2, 4], [6, 4, 8, 3], [9, 15, 8, 2], [0, 0, 5, 3], [4, 11, 5, 4], [13, 0, 3, 3]],
    1],
   [2, 5]),
  ('partial repair boundary #1',
   [18,
    25,
    [[4, 22, 5, 2], [7, 7, 3, 3], [2, -1, 3, 6], [5, 14, 8, 3], [4, 19, 5, 6], [8, 23, 3, 6], [0, 3, 2, 2]],
    1],
   [1, 3]),
  ('partial repair boundary #2',
   [22,
    11,
    [[0, 0, 4, 2],
     [4, 7, 8, 4],
     [19, 6, 4, 6],
     [11, 7, 2, 4],
     [10, -1, 5, 4],
     [13, 9, 4, 4],
     [10, 1, 8, 4],
     [19, 9, 4, 3]],
    1],
   [6]),
  ('touching border tile #1', [10, 10, [[1, 1, 8, 8]], 1], [0]),
  ('rooms exactly pad apart #1', [20, 10, [[1, 1, 4, 4], [6, 1, 4, 4]], 1], [0, 1]),
  ('control #1', [9, 21, [[1, 11, 2, 4], [1, 3, 5, 2], [3, 3, 8, 6], [-1, 5, 4, 3]], 1], []),
  ('control #2',
   [11, 28, [[1, 8, 8, 4], [5, 14, 3, 3], [1, 4, 5, 3], [7, 23, 2, 2], [-1, 11, 5, 2]], 2],
   [0, 1])],
 [('regression near border #1',
   [29,
    11,
    [[19, 6, 4, 6],
     [9, 5, 3, 4],
     [1, 1, 3, 2],
     [5, 4, 5, 6],
     [14, 0, 8, 3],
     [1, 8, 5, 6],
     [5, 5, 3, 3],
     [7, 2, 2, 3]],
    1],
   [1, 6]),
  ('regression near border #2',
   [16, 18, [[4, 0, 3, 3], [0, 7, 8, 3], [11, 15, 3, 2], [1, 7, 5, 2], [10, 11, 5, 6]], 1],
   [4]),
  ('regression near border #3',
   [19,
    18,
    [[15, 0, 4, 3], [6, 4, 2, 4], [6, 4, 8, 3], [9, 15, 8, 2], [0, 0, 5, 3], [4, 11, 5, 4], [13, 0, 3, 3]],
    1],
   [2, 5]),
  ('partial repair boundary #1',
   [17, 29, [[-1, 4, 2, 6], [8, 13, 2, 3], [1, -1, 3, 3], [12, 1, 8, 6], [4, 18, 3, 2], [13, -1, 8, 2]], 2],
   []),
  ('thin corridor room #1', [20, 20, [[2, 2, 2, 9], [2, 2, 5, 5]], 0], [1]),
  ('touching border tile #1', [10, 10, [[1, 1, 8, 8]], 1], [0]),
  ('control #1',
   [24, 17, [[21, 15, 8, 3], [1, 9, 3, 4], [1, 9, 5, 2], [1, 1, 5, 2], [20, 13, 5, 6]], 2],
   [1]),
  ('control #2', [10, 15, [[-1, 9, 5, 2]], 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
fault site near border #1[4][]Failed
regression near border #1[0, 2, 5][0, 5]Failed
partial repair boundary #1[2][2]Passed
partial repair boundary #2[0, 1, 5][0, 1, 5]Passed
touching border tile #1[0][0]Passed
rooms exactly pad apart #1[0, 1][0, 1]Passed
thin corridor room #1[1][1]Passed
control #1[0, 2][0, 2]Passed

SHA-256 / e8b00b7a678d1092c843e05bbd34736acd8d9eaa4c6ccd9a64917f3d85641bf7

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(width, height, candidates, pad):
    placed = []
    out = []
    for i, (x, y, w, h) in enumerate(candidates):
        if w < 3 or h < 3:
            continue
        if x < 1 or x + w > width - 1 or y + h > height - 1:
            continue
        ok = True
        for px, py, pw, ph in placed:
            if x < px + pw + pad and px < x + w + pad and y < py + ph + pad and py < y + h + pad:
                ok = False
                break
        if ok:
            placed.append((x, y, w, h))
            out.append(i)
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = [[('fault site near border #1',
   [13,
    21,
    [[9, 8, 5, 3], [11, 14, 8, 3], [7, 15, 3, 2], [-1, 10, 8, 6], [0, 3, 3, 3], [10, 0, 5, 6], [8, 13, 2, 4]],
    2],
   []),
  ('regression near border #1',
   [16,
    30,
    [[12, 13, 3, 6],
     [11, 9, 5, 3],
     [1, 0, 5, 3],
     [14, 10, 8, 3],
     [13, 19, 8, 4],
     [6, 14, 5, 6],
     [8, 18, 5, 2]],
    1],
   [0, 5]),
  ('partial repair boundary #1',
   [30, 11, [[-1, 1, 2, 2], [24, -1, 5, 3], [16, 4, 5, 6], [3, 1, 2, 6], [26, 2, 2, 3], [5, 9, 8, 2]], 0],
   [2]),
  ('partial repair boundary #2',
   [27,
    21,
    [[17, 14, 4, 3],
     [16, 17, 4, 3],
     [23, -1, 5, 3],
     [21, -1, 4, 4],
     [19, 6, 8, 6],
     [7, 11, 3, 3],
     [3, 2, 5, 2],
     [4, -1, 5, 3]],
    0],
   [0, 1, 5]),
  ('touching border tile #1', [10, 10, [[1, 1, 8, 8]], 1], [0]),
  ('rooms exactly pad apart #1', [20, 10, [[1, 1, 4, 4], [6, 1, 4, 4]], 1], [0, 1]),
  ('thin corridor room #1', [20, 20, [[2, 2, 2, 9], [2, 2, 5, 5]], 0], [1]),
  ('control #1',
   [25,
    23,
    [[5, 9, 3, 6],
     [8, 10, 5, 6],
     [9, 14, 5, 4],
     [-1, 1, 3, 6],
     [-1, 14, 2, 3],
     [17, 18, 4, 2],
     [4, 20, 3, 4]],
    1],
   [0, 2])],
 [('fault site near border #1', [8, 25, [[0, 8, 3, 6], [4, -1, 4, 3], [1, 17, 5, 2]], 1], []),
  ('fault site near border #2',
   [14,
    21,
    [[7, 6, 3, 6], [11, -1, 8, 2], [0, 12, 3, 3], [-1, 14, 8, 6], [6, 9, 3, 4], [1, 10, 4, 4], [9, 19, 2, 2]],
    0],
   [0, 5]),
  ('partial repair boundary #1',
   [26, 13, [[7, 10, 8, 4], [22, -1, 3, 6], [3, 3, 4, 6], [17, 0, 8, 2]], 1],
   [2]),
  ('regression near border #1',
   [16,
    30,
    [[12, 13, 3, 6],
     [11, 9, 5, 3],
     [1, 0, 5, 3],
     [14, 10, 8, 3],
     [13, 19, 8, 4],
     [6, 14, 5, 6],
     [8, 18, 5, 2]],
    1],
   [0, 5]),
  ('thin corridor room #1', [20, 20, [[2, 2, 2, 9], [2, 2, 5, 5]], 0], [1]),
  ('touching border tile #1', [10, 10, [[1, 1, 8, 8]], 1], [0]),
  ('control #1',
   [25,
    23,
    [[5, 9, 3, 6],
     [8, 10, 5, 6],
     [9, 14, 5, 4],
     [-1, 1, 3, 6],
     [-1, 14, 2, 3],
     [17, 18, 4, 2],
     [4, 20, 3, 4]],
    1],
   [0, 2]),
  ('control #2',
   [19, 27, [[6, 2, 3, 2], [4, 23, 5, 4], [4, 20, 2, 3], [12, 4, 8, 2], [10, 14, 8, 6]], 1],
   [4])],
 [('fault site near border #1',
   [16,
    29,
    [[4, 0, 2, 3], [10, 16, 4, 6], [5, 21, 3, 6], [1, 9, 3, 3], [0, 22, 4, 3], [-1, 21, 4, 6], [14, 4, 5, 2]],
    1],
   [1, 2, 3]),
  ('fault site near border #2',
   [29, 27, [[19, 5, 8, 3], [3, 14, 5, 3], [0, 20, 4, 4], [-1, 5, 3, 4], [0, 7, 5, 2]], 0],
   [0, 1]),
  ('partial repair boundary #1',
   [10, 8, [[7, 3, 3, 3], [2, 3, 5, 3], [5, 6, 5, 6], [6, 3, 3, 6], [8, 3, 2, 3], [2, -1, 4, 4]], 0],
   [1]),
  ('regression near border #1',
   [18,
    19,
    [[7, 11, 4, 2],
     [2, 8, 8, 2],
     [14, 9, 3, 3],
     [8, 8, 5, 2],
     [7, 13, 3, 2],
     [10, 12, 8, 2],
     [14, 5, 8, 4],
     [5, 0, 5, 4]],
    1],
   [2]),
  ('rooms exactly pad apart #1', [20, 10, [[1, 1, 4, 4], [6, 1, 4, 4]], 1], [0, 1]),
  ('thin corridor room #1', [20, 20, [[2, 2, 2, 9], [2, 2, 5, 5]], 0], [1]),
  ('control #1',
   [19, 27, [[6, 2, 3, 2], [4, 23, 5, 4], [4, 20, 2, 3], [12, 4, 8, 2], [10, 14, 8, 6]], 1],
   [4]),
  ('control #2', [15, 13, [[6, 11, 5, 6], [-1, 3, 2, 4]], 1], [])],
 [('regression near border #1',
   [18,
    19,
    [[7, 11, 4, 2],
     [2, 8, 8, 2],
     [14, 9, 3, 3],
     [8, 8, 5, 2],
     [7, 13, 3, 2],
     [10, 12, 8, 2],
     [14, 5, 8, 4],
     [5, 0, 5, 4]],
    1],
   [2]),
  ('regression near border #2',
   [19,
    18,
    [[15, 0, 4, 3], [6, 4, 2, 4], [6, 4, 8, 3], [9, 15, 8, 2], [0, 0, 5, 3], [4, 11, 5, 4], [13, 0, 3, 3]],
    1],
   [2, 5]),
  ('partial repair boundary #1',
   [18,
    25,
    [[4, 22, 5, 2], [7, 7, 3, 3], [2, -1, 3, 6], [5, 14, 8, 3], [4, 19, 5, 6], [8, 23, 3, 6], [0, 3, 2, 2]],
    1],
   [1, 3]),
  ('partial repair boundary #2',
   [22,
    11,
    [[0, 0, 4, 2],
     [4, 7, 8, 4],
     [19, 6, 4, 6],
     [11, 7, 2, 4],
     [10, -1, 5, 4],
     [13, 9, 4, 4],
     [10, 1, 8, 4],
     [19, 9, 4, 3]],
    1],
   [6]),
  ('touching border tile #1', [10, 10, [[1, 1, 8, 8]], 1], [0]),
  ('rooms exactly pad apart #1', [20, 10, [[1, 1, 4, 4], [6, 1, 4, 4]], 1], [0, 1]),
  ('control #1', [9, 21, [[1, 11, 2, 4], [1, 3, 5, 2], [3, 3, 8, 6], [-1, 5, 4, 3]], 1], []),
  ('control #2',
   [11, 28, [[1, 8, 8, 4], [5, 14, 3, 3], [1, 4, 5, 3], [7, 23, 2, 2], [-1, 11, 5, 2]], 2],
   [0, 1])],
 [('regression near border #1',
   [29,
    11,
    [[19, 6, 4, 6],
     [9, 5, 3, 4],
     [1, 1, 3, 2],
     [5, 4, 5, 6],
     [14, 0, 8, 3],
     [1, 8, 5, 6],
     [5, 5, 3, 3],
     [7, 2, 2, 3]],
    1],
   [1, 6]),
  ('regression near border #2',
   [16, 18, [[4, 0, 3, 3], [0, 7, 8, 3], [11, 15, 3, 2], [1, 7, 5, 2], [10, 11, 5, 6]], 1],
   [4]),
  ('regression near border #3',
   [19,
    18,
    [[15, 0, 4, 3], [6, 4, 2, 4], [6, 4, 8, 3], [9, 15, 8, 2], [0, 0, 5, 3], [4, 11, 5, 4], [13, 0, 3, 3]],
    1],
   [2, 5]),
  ('partial repair boundary #1',
   [17, 29, [[-1, 4, 2, 6], [8, 13, 2, 3], [1, -1, 3, 3], [12, 1, 8, 6], [4, 18, 3, 2], [13, -1, 8, 2]], 2],
   []),
  ('thin corridor room #1', [20, 20, [[2, 2, 2, 9], [2, 2, 5, 5]], 0], [1]),
  ('touching border tile #1', [10, 10, [[1, 1, 8, 8]], 1], [0]),
  ('control #1',
   [24, 17, [[21, 15, 8, 3], [1, 9, 3, 4], [1, 9, 5, 2], [1, 1, 5, 2], [20, 13, 5, 6]], 2],
   [1]),
  ('control #2', [10, 15, [[-1, 9, 5, 2]], 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
fault site near border #1[][]Passed
regression near border #1[0, 2, 5][0, 5]Failed
partial repair boundary #1[1, 2][2]Failed
partial repair boundary #2[0, 1, 3, 5, 7][0, 1, 5]Failed
touching border tile #1[0][0]Passed
rooms exactly pad apart #1[0, 1][0, 1]Passed
thin corridor room #1[1][1]Passed
control #1[0, 2][0, 2]Passed

SHA-256 / fe97b567b162aa5dd82b101556aafb9b615c708a7862766e225ecde2288575aa

3 / The verified repair

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

N = 1
observations = []
def solve(width, height, candidates, pad):
    placed = []
    out = []
    for i, (x, y, w, h) in enumerate(candidates):
        if w < 3 or h < 3:
            continue
        if x < 1 or y < 1 or x + w > width - 1 or y + h > height - 1:
            continue
        ok = True
        for px, py, pw, ph in placed:
            if x < px + pw + pad and px < x + w + pad and y < py + ph + pad and py < y + h + pad:
                ok = False
                break
        if ok:
            placed.append((x, y, w, h))
            out.append(i)
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = [[('fault site near border #1',
   [13,
    21,
    [[9, 8, 5, 3], [11, 14, 8, 3], [7, 15, 3, 2], [-1, 10, 8, 6], [0, 3, 3, 3], [10, 0, 5, 6], [8, 13, 2, 4]],
    2],
   []),
  ('regression near border #1',
   [16,
    30,
    [[12, 13, 3, 6],
     [11, 9, 5, 3],
     [1, 0, 5, 3],
     [14, 10, 8, 3],
     [13, 19, 8, 4],
     [6, 14, 5, 6],
     [8, 18, 5, 2]],
    1],
   [0, 5]),
  ('partial repair boundary #1',
   [30, 11, [[-1, 1, 2, 2], [24, -1, 5, 3], [16, 4, 5, 6], [3, 1, 2, 6], [26, 2, 2, 3], [5, 9, 8, 2]], 0],
   [2]),
  ('partial repair boundary #2',
   [27,
    21,
    [[17, 14, 4, 3],
     [16, 17, 4, 3],
     [23, -1, 5, 3],
     [21, -1, 4, 4],
     [19, 6, 8, 6],
     [7, 11, 3, 3],
     [3, 2, 5, 2],
     [4, -1, 5, 3]],
    0],
   [0, 1, 5]),
  ('touching border tile #1', [10, 10, [[1, 1, 8, 8]], 1], [0]),
  ('rooms exactly pad apart #1', [20, 10, [[1, 1, 4, 4], [6, 1, 4, 4]], 1], [0, 1]),
  ('thin corridor room #1', [20, 20, [[2, 2, 2, 9], [2, 2, 5, 5]], 0], [1]),
  ('control #1',
   [25,
    23,
    [[5, 9, 3, 6],
     [8, 10, 5, 6],
     [9, 14, 5, 4],
     [-1, 1, 3, 6],
     [-1, 14, 2, 3],
     [17, 18, 4, 2],
     [4, 20, 3, 4]],
    1],
   [0, 2])],
 [('fault site near border #1', [8, 25, [[0, 8, 3, 6], [4, -1, 4, 3], [1, 17, 5, 2]], 1], []),
  ('fault site near border #2',
   [14,
    21,
    [[7, 6, 3, 6], [11, -1, 8, 2], [0, 12, 3, 3], [-1, 14, 8, 6], [6, 9, 3, 4], [1, 10, 4, 4], [9, 19, 2, 2]],
    0],
   [0, 5]),
  ('partial repair boundary #1',
   [26, 13, [[7, 10, 8, 4], [22, -1, 3, 6], [3, 3, 4, 6], [17, 0, 8, 2]], 1],
   [2]),
  ('regression near border #1',
   [16,
    30,
    [[12, 13, 3, 6],
     [11, 9, 5, 3],
     [1, 0, 5, 3],
     [14, 10, 8, 3],
     [13, 19, 8, 4],
     [6, 14, 5, 6],
     [8, 18, 5, 2]],
    1],
   [0, 5]),
  ('thin corridor room #1', [20, 20, [[2, 2, 2, 9], [2, 2, 5, 5]], 0], [1]),
  ('touching border tile #1', [10, 10, [[1, 1, 8, 8]], 1], [0]),
  ('control #1',
   [25,
    23,
    [[5, 9, 3, 6],
     [8, 10, 5, 6],
     [9, 14, 5, 4],
     [-1, 1, 3, 6],
     [-1, 14, 2, 3],
     [17, 18, 4, 2],
     [4, 20, 3, 4]],
    1],
   [0, 2]),
  ('control #2',
   [19, 27, [[6, 2, 3, 2], [4, 23, 5, 4], [4, 20, 2, 3], [12, 4, 8, 2], [10, 14, 8, 6]], 1],
   [4])],
 [('fault site near border #1',
   [16,
    29,
    [[4, 0, 2, 3], [10, 16, 4, 6], [5, 21, 3, 6], [1, 9, 3, 3], [0, 22, 4, 3], [-1, 21, 4, 6], [14, 4, 5, 2]],
    1],
   [1, 2, 3]),
  ('fault site near border #2',
   [29, 27, [[19, 5, 8, 3], [3, 14, 5, 3], [0, 20, 4, 4], [-1, 5, 3, 4], [0, 7, 5, 2]], 0],
   [0, 1]),
  ('partial repair boundary #1',
   [10, 8, [[7, 3, 3, 3], [2, 3, 5, 3], [5, 6, 5, 6], [6, 3, 3, 6], [8, 3, 2, 3], [2, -1, 4, 4]], 0],
   [1]),
  ('regression near border #1',
   [18,
    19,
    [[7, 11, 4, 2],
     [2, 8, 8, 2],
     [14, 9, 3, 3],
     [8, 8, 5, 2],
     [7, 13, 3, 2],
     [10, 12, 8, 2],
     [14, 5, 8, 4],
     [5, 0, 5, 4]],
    1],
   [2]),
  ('rooms exactly pad apart #1', [20, 10, [[1, 1, 4, 4], [6, 1, 4, 4]], 1], [0, 1]),
  ('thin corridor room #1', [20, 20, [[2, 2, 2, 9], [2, 2, 5, 5]], 0], [1]),
  ('control #1',
   [19, 27, [[6, 2, 3, 2], [4, 23, 5, 4], [4, 20, 2, 3], [12, 4, 8, 2], [10, 14, 8, 6]], 1],
   [4]),
  ('control #2', [15, 13, [[6, 11, 5, 6], [-1, 3, 2, 4]], 1], [])],
 [('regression near border #1',
   [18,
    19,
    [[7, 11, 4, 2],
     [2, 8, 8, 2],
     [14, 9, 3, 3],
     [8, 8, 5, 2],
     [7, 13, 3, 2],
     [10, 12, 8, 2],
     [14, 5, 8, 4],
     [5, 0, 5, 4]],
    1],
   [2]),
  ('regression near border #2',
   [19,
    18,
    [[15, 0, 4, 3], [6, 4, 2, 4], [6, 4, 8, 3], [9, 15, 8, 2], [0, 0, 5, 3], [4, 11, 5, 4], [13, 0, 3, 3]],
    1],
   [2, 5]),
  ('partial repair boundary #1',
   [18,
    25,
    [[4, 22, 5, 2], [7, 7, 3, 3], [2, -1, 3, 6], [5, 14, 8, 3], [4, 19, 5, 6], [8, 23, 3, 6], [0, 3, 2, 2]],
    1],
   [1, 3]),
  ('partial repair boundary #2',
   [22,
    11,
    [[0, 0, 4, 2],
     [4, 7, 8, 4],
     [19, 6, 4, 6],
     [11, 7, 2, 4],
     [10, -1, 5, 4],
     [13, 9, 4, 4],
     [10, 1, 8, 4],
     [19, 9, 4, 3]],
    1],
   [6]),
  ('touching border tile #1', [10, 10, [[1, 1, 8, 8]], 1], [0]),
  ('rooms exactly pad apart #1', [20, 10, [[1, 1, 4, 4], [6, 1, 4, 4]], 1], [0, 1]),
  ('control #1', [9, 21, [[1, 11, 2, 4], [1, 3, 5, 2], [3, 3, 8, 6], [-1, 5, 4, 3]], 1], []),
  ('control #2',
   [11, 28, [[1, 8, 8, 4], [5, 14, 3, 3], [1, 4, 5, 3], [7, 23, 2, 2], [-1, 11, 5, 2]], 2],
   [0, 1])],
 [('regression near border #1',
   [29,
    11,
    [[19, 6, 4, 6],
     [9, 5, 3, 4],
     [1, 1, 3, 2],
     [5, 4, 5, 6],
     [14, 0, 8, 3],
     [1, 8, 5, 6],
     [5, 5, 3, 3],
     [7, 2, 2, 3]],
    1],
   [1, 6]),
  ('regression near border #2',
   [16, 18, [[4, 0, 3, 3], [0, 7, 8, 3], [11, 15, 3, 2], [1, 7, 5, 2], [10, 11, 5, 6]], 1],
   [4]),
  ('regression near border #3',
   [19,
    18,
    [[15, 0, 4, 3], [6, 4, 2, 4], [6, 4, 8, 3], [9, 15, 8, 2], [0, 0, 5, 3], [4, 11, 5, 4], [13, 0, 3, 3]],
    1],
   [2, 5]),
  ('partial repair boundary #1',
   [17, 29, [[-1, 4, 2, 6], [8, 13, 2, 3], [1, -1, 3, 3], [12, 1, 8, 6], [4, 18, 3, 2], [13, -1, 8, 2]], 2],
   []),
  ('thin corridor room #1', [20, 20, [[2, 2, 2, 9], [2, 2, 5, 5]], 0], [1]),
  ('touching border tile #1', [10, 10, [[1, 1, 8, 8]], 1], [0]),
  ('control #1',
   [24, 17, [[21, 15, 8, 3], [1, 9, 3, 4], [1, 9, 5, 2], [1, 1, 5, 2], [20, 13, 5, 6]], 2],
   [1]),
  ('control #2', [10, 15, [[-1, 9, 5, 2]], 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
fault site near border #1[][]Passed
regression near border #1[0, 5][0, 5]Passed
partial repair boundary #1[2][2]Passed
partial repair boundary #2[0, 1, 5][0, 1, 5]Passed
touching border tile #1[0][0]Passed
rooms exactly pad apart #1[0, 1][0, 1]Passed
thin corridor room #1[1][1]Passed
control #1[0, 2][0, 2]Passed

SHA-256 / e478a52e6136269d32b2c0d50c2a98a2ee1f534b995344c6042f2cc6f9baf371

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 2026-09-29T14:50:48.792488+00:00.

Case digest / d898b9967a61629b5933ef6b1472568bf6aeac9a017dc1da70d7856d65dd88ae