FA-82876 / Go territory scoring / Open access

Territory flood fill consults the unmodified board · case 01

Regions that should absorb removed dead stones stay neutral.

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

ROOT CAUSE

The neighbour test reads the original board rather than the board with dead stones removed.

VERIFIED REPAIR

Read neighbours and seeds from the working copy g after removal.

Unsuccessful approach: Reading neighbours from g but seeding regions from the original board misses dead stones enclosed only by stones.

Case contract

Input [board, dead_points, prisoners_held_by_black, prisoners_held_by_white, komi_tenths]. Each listed dead stone is removed once and becomes a prisoner of its opponent (duplicates and empty points are ignored). Territory = empty regions (after removal) bordered by one colour only. Return [terr_b, terr_w, pris_b, pris_w, result] with result "B+x.y", "W+x.y" or "Jigo".

Why this case matters

Go servers and scoring tools compute this value automatically; a wrong answer changes a game result.

1 / The failure

Exit 1

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

N = 1
observations = []
def solve(x):
    board, dead, capb, capw, komi = x
    g = [list(row) for row in board]
    pb = capb
    pw = capw
    for r, c in dead:
        if g[r][c] == 'B':
            pw += 1
        elif g[r][c] == 'W':
            pb += 1
        g[r][c] = '.'
    n = len(g)
    m = len(g[0])
    tb = 0
    tw = 0
    seen = set()
    for r in range(n):
        for c in range(m):
            if g[r][c] != '.' or (r, c) in seen:
                continue
            stack = [(r, c)]
            seen.add((r, c))
            size = 0
            owners = set()
            while stack:
                i, j = stack.pop()
                size += 1
                for p, q in ((i + 1, j), (i - 1, j), (i, j + 1), (i, j - 1)):
                    if 0 <= p < n and 0 <= q < m:
                        if board[p][q] == '.':
                            if (p, q) not in seen:
                                seen.add((p, q))
                                stack.append((p, q))
                        else:
                            owners.add(g[p][q])
            if owners == {'B'}:
                tb += size
            elif owners == {'W'}:
                tw += size
    sb = (tb + pb) * 10
    sw = (tw + pw) * 10 + komi
    if sb > sw:
        res = 'B+%d.%d' % ((sb - sw) // 10, (sb - sw) % 10)
    elif sw > sb:
        res = 'W+%d.%d' % ((sw - sb) // 10, (sw - sb) % 10)
    else:
        res = 'Jigo'
    return [tb, tw, pb, pw, res]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[[[['.WBW..', '..BW.B', '..BW..', '..BW..', '..BWB.', 'WWBW..'], [[4, 4], [0, 1], [4, 4]], 4, 4, 60], [0, 0, 5, 5, 'W+6.0']], [[['..WBW', '...BW', '...BW', 'W..BW'], [[0, 3], [3, 4], [3, 0]], 3, 0, 65], [0, 0, 5, 1, 'W+2.5']], [[['..BW.', '..BW.', '..BW.', '..BWB', '..BW.', '..BW.'], [[3, 2], [3, 2]], 1, 1, 0], [0, 0, 1, 2, 'W+1.0']], [[['.BW.B..', '.BW....', '.BW....', '.BW.B..', '.BW....', '.BW.B..', '.BW....'], [[4, 2], [2, 1], [6, 1]], 3, 0, 0], [0, 0, 4, 2, 'B+2.0']], [[['.....BW', '....WBW', '.W...BW', '..W..BW', '...W.BW'], [[4, 5]], 0, 0, 65], [0, 0, 0, 1, 'W+7.5']], [[['W..BW.', '..WBW.', 'W..BW.', '...BW.', '...BW.', '..WBW.'], [[1, 2], [5, 2], [0, 4]], 0, 3, 5], [0, 0, 3, 3, 'W+0.5']], [[['W.BW..', 'W.BW..', '..BW..', '.WBW..', '..BW..', '..BW..', '..BW..'], [[3, 2]], 3, 3, 0], [0, 14, 3, 4, 'W+15.0']], [[['BBB', 'BWB', 'BBB'], [[1, 1], [1, 1]], 1, 0, 65], [1, 0, 2, 0, 'W+3.5']]], [[[['W.BW..', '..BW..', '..BW..', '.WBW.B', 'W.BW..', '..BW..', '.WBW..'], [[1, 2], [3, 2], [5, 0]], 2, 0, 55], [0, 0, 2, 2, 'W+5.5']], [[['....BW.', '....BW.', '.W..BW.', '...WBW.', '...WBWB', '....BW.'], [[5, 1]], 4, 3, 55], [0, 0, 4, 3, 'W+4.5']], [[['...BW..', '...BWB.', '...BW..', '...BW..', '...BW..'], [[0, 3], [0, 3], [4, 2]], 0, 1, 5], [0, 0, 0, 2, 'W+2.5']], [[['..BW', '.WBW', '..BW', '..BW'], [[3, 2], [0, 3], [3, 2]], 0, 4, 60], [0, 0, 1, 5, 'W+10.0']], [[['....BWB', '....BW.', '....BW.', '....BWB'], [[2, 5]], 4, 1, 0], [16, 0, 5, 1, 'B+20.0']], [[['.BW.', '.BW.', '.BW.', '.BW.'], [[3, 1]], 1, 1, 60], [0, 4, 1, 2, 'W+11.0']], [[['....BW.', 'W..WBW.', 'W...BW.', '..W.BW.', '....BW.', '....BW.'], [[3, 4], [4, 4], [1, 0], [2, 3]], 1, 3, 65], [0, 6, 2, 5, 'W+15.5']], [[['W..BWW', 'BBW..W', '..WB..', '....WB', 'WWWWW.', 'WWB...'], [[0, 5], [4, 5]], 2, 2, 55], [0, 1, 3, 2, 'W+5.5']]], [[[['..BW', '..BW', '.WBW', '.WBW', '..BW'], [[0, 3], [4, 2], [3, 0]], 0, 0, 60], [0, 0, 1, 1, 'W+6.0']], [[['.BW.', '.BW.', '.BW.', '.BW.', '.BWB', '.BWB', 'WBW.'], [[4, 1], [4, 1]], 0, 2, 0], [0, 0, 0, 3, 'W+3.0']], [[['W.BW...', '.WBW...', '..BW..B', '..BW...', '.WBWB..', '..BW...'], [[4, 4], [4, 0]], 3, 1, 55], [0, 0, 3, 2, 'W+4.5']], [[['WBW.B..', '.BW.B..', '.BWBB..', 'WBW....', '.BW.B..', '.BW.B..', 'WBW....'], [[2, 2], [6, 2], [2, 2]], 0, 1, 5], [0, 0, 2, 1, 'B+0.5']], [[['..BW', '.WBW', '..BW', '..BW', '..BW', '..BW'], [[1, 3], [3, 3], [1, 3]], 4, 1, 55], [0, 0, 6, 1, 'W+0.5']], [[['.....BW', '.....BW', '.....BW', '.W...BW', '.....BW'], [[3, 5], [1, 5], [3, 6], [3, 5]], 0, 3, 5], [0, 0, 1, 5, 'W+4.5']], [[['..B..', '..B..', 'BBBBB', 'WWWWW', '..W..'], [[4, 2]], 4, 3, 55], [8, 5, 5, 3, 'W+0.5']], [[['..W.W', 'B.BB.', 'BBB..'], [[0, 4], [2, 0]], 1, 1, 65], [1, 0, 2, 2, 'W+5.5']]], [[[['W..BWB', '...BW.', '...BW.', '...BWB'], [[0, 5]], 4, 0, 5], [0, 0, 4, 1, 'B+2.5']], [[['W...BW', '....BW', '....BW', '....BW', '....BW'], [[0, 0], [0, 4]], 0, 0, 5], [0, 0, 1, 1, 'W+0.5']], [[['..BWB', '..BWB', 'W.BW.', '..BW.', '..BW.'], [], 2, 4, 55], [0, 0, 2, 4, 'W+7.5']], [[['.BW..', 'WBWB.', '.BW..', 'WBW..', '.BW..'], [[2, 1], [3, 1]], 2, 2, 0], [0, 0, 2, 4, 'W+2.0']], [[['..BW...', '..BWB..', '.WBW...', '..BW.B.', 'W.BW...', '..BW...', '..BWBB.'], [[6, 2]], 2, 0, 65], [0, 0, 2, 1, 'W+5.5']], [[['.BW..', '.BW..', '.BW..', '.BW..', '.BWB.', '.BW..', 'WBW..'], [[0, 2], [0, 2]], 0, 2, 0], [0, 0, 1, 2, 'W+1.0']], [[['BBBB', 'B..B', 'B..B', 'BBBB'], [[2, 0], [1, 3], [2, 0]], 0, 4, 5], [6, 0, 0, 6, 'W+0.5']], [[['WWW', 'W.W', 'WWW'], [[0, 1], [2, 2]], 1, 3, 65], [0, 3, 3, 3, 'W+9.5']]], [[[['...BWB.', '...BW..', '...BW..', '...BW..', '...BW..'], [[1, 4], [2, 4], [4, 3]], 2, 1, 5], [0, 0, 4, 2, 'B+1.5']], [[['...BWBB', 'W..BW..', '..WBW..', '...BW..', '...BW.B', '...BWB.'], [[3, 4]], 2, 4, 5], [1, 0, 3, 4, 'W+0.5']], [[['.BW...', '.BWB..', '.BW...', '.BW...', '.BW...', '.BW...', '.BW.BB'], [[1, 1], [1, 1], [2, 4]], 4, 1, 60], [0, 0, 4, 2, 'W+4.0']], [[['...BW', '...BW', 'W..BW', '...BW', '.W.BW', '...BW', 'W..BW'], [], 1, 1, 0], [0, 0, 1, 1, 'Jigo']], [[['....BW.', 'W..WBW.', 'W...BW.', '..W.BW.', '....BW.', '....BW.'], [[3, 4], [4, 4], [1, 0], [2, 3]], 1, 3, 65], [0, 6, 2, 5, 'W+15.5']], [[['....', '....', '....', '....'], [], 4, 0, 60], [0, 0, 4, 0, 'W+2.0']], [[['..W', '.W.', 'W..'], [[0, 2], [2, 0]], 3, 2, 60], [0, 8, 5, 2, 'W+11.0']], [[['BBB', 'BWB', 'BBB'], [[1, 1]], 0, 0, 0], [1, 0, 1, 0, 'B+2.0']]]]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check("territory score case %d" % i, 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 fixture	Actual	Expected	Outcome
territory score case 0	`[1, 1, 5, 5, 'W+6.0']`	`[0, 0, 5, 5, 'W+6.0']`	Failed
territory score case 1	`[0, 0, 5, 1, 'W+2.5']`	`[0, 0, 5, 1, 'W+2.5']`	Passed
territory score case 2	`[0, 0, 1, 2, 'W+1.0']`	`[0, 0, 1, 2, 'W+1.0']`	Passed
territory score case 3	`[0, 0, 4, 2, 'B+2.0']`	`[0, 0, 4, 2, 'B+2.0']`	Passed
territory score case 4	`[0, 0, 0, 1, 'W+7.5']`	`[0, 0, 0, 1, 'W+7.5']`	Passed
territory score case 5	`[2, 0, 3, 3, 'B+1.5']`	`[0, 0, 3, 3, 'W+0.5']`	Failed
territory score case 6	`[0, 14, 3, 4, 'W+15.0']`	`[0, 14, 3, 4, 'W+15.0']`	Passed
territory score case 7	`[1, 0, 2, 0, 'W+3.5']`	`[1, 0, 2, 0, 'W+3.5']`	Passed

SHA-256 / acdb83bfc1997e51b5efb0e38eeaba602bd6b55473b7ba3efd37e2df9f4f102f

2 / The unsuccessful fix

Exit 1

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

N = 1
observations = []
def solve(x):
    board, dead, capb, capw, komi = x
    g = [list(row) for row in board]
    pb = capb
    pw = capw
    for r, c in dead:
        if g[r][c] == 'B':
            pw += 1
        elif g[r][c] == 'W':
            pb += 1
        g[r][c] = '.'
    n = len(g)
    m = len(g[0])
    tb = 0
    tw = 0
    seen = set()
    for r in range(n):
        for c in range(m):
            if board[r][c] != '.' or (r, c) in seen:
                continue
            stack = [(r, c)]
            seen.add((r, c))
            size = 0
            owners = set()
            while stack:
                i, j = stack.pop()
                size += 1
                for p, q in ((i + 1, j), (i - 1, j), (i, j + 1), (i, j - 1)):
                    if 0 <= p < n and 0 <= q < m:
                        if g[p][q] == '.':
                            if (p, q) not in seen:
                                seen.add((p, q))
                                stack.append((p, q))
                        else:
                            owners.add(g[p][q])
            if owners == {'B'}:
                tb += size
            elif owners == {'W'}:
                tw += size
    sb = (tb + pb) * 10
    sw = (tw + pw) * 10 + komi
    if sb > sw:
        res = 'B+%d.%d' % ((sb - sw) // 10, (sb - sw) % 10)
    elif sw > sb:
        res = 'W+%d.%d' % ((sw - sb) // 10, (sw - sb) % 10)
    else:
        res = 'Jigo'
    return [tb, tw, pb, pw, res]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[[[['.WBW..', '..BW.B', '..BW..', '..BW..', '..BWB.', 'WWBW..'], [[4, 4], [0, 1], [4, 4]], 4, 4, 60], [0, 0, 5, 5, 'W+6.0']], [[['..WBW', '...BW', '...BW', 'W..BW'], [[0, 3], [3, 4], [3, 0]], 3, 0, 65], [0, 0, 5, 1, 'W+2.5']], [[['..BW.', '..BW.', '..BW.', '..BWB', '..BW.', '..BW.'], [[3, 2], [3, 2]], 1, 1, 0], [0, 0, 1, 2, 'W+1.0']], [[['.BW.B..', '.BW....', '.BW....', '.BW.B..', '.BW....', '.BW.B..', '.BW....'], [[4, 2], [2, 1], [6, 1]], 3, 0, 0], [0, 0, 4, 2, 'B+2.0']], [[['.....BW', '....WBW', '.W...BW', '..W..BW', '...W.BW'], [[4, 5]], 0, 0, 65], [0, 0, 0, 1, 'W+7.5']], [[['W..BW.', '..WBW.', 'W..BW.', '...BW.', '...BW.', '..WBW.'], [[1, 2], [5, 2], [0, 4]], 0, 3, 5], [0, 0, 3, 3, 'W+0.5']], [[['W.BW..', 'W.BW..', '..BW..', '.WBW..', '..BW..', '..BW..', '..BW..'], [[3, 2]], 3, 3, 0], [0, 14, 3, 4, 'W+15.0']], [[['BBB', 'BWB', 'BBB'], [[1, 1], [1, 1]], 1, 0, 65], [1, 0, 2, 0, 'W+3.5']]], [[[['W.BW..', '..BW..', '..BW..', '.WBW.B', 'W.BW..', '..BW..', '.WBW..'], [[1, 2], [3, 2], [5, 0]], 2, 0, 55], [0, 0, 2, 2, 'W+5.5']], [[['....BW.', '....BW.', '.W..BW.', '...WBW.', '...WBWB', '....BW.'], [[5, 1]], 4, 3, 55], [0, 0, 4, 3, 'W+4.5']], [[['...BW..', '...BWB.', '...BW..', '...BW..', '...BW..'], [[0, 3], [0, 3], [4, 2]], 0, 1, 5], [0, 0, 0, 2, 'W+2.5']], [[['..BW', '.WBW', '..BW', '..BW'], [[3, 2], [0, 3], [3, 2]], 0, 4, 60], [0, 0, 1, 5, 'W+10.0']], [[['....BWB', '....BW.', '....BW.', '....BWB'], [[2, 5]], 4, 1, 0], [16, 0, 5, 1, 'B+20.0']], [[['.BW.', '.BW.', '.BW.', '.BW.'], [[3, 1]], 1, 1, 60], [0, 4, 1, 2, 'W+11.0']], [[['....BW.', 'W..WBW.', 'W...BW.', '..W.BW.', '....BW.', '....BW.'], [[3, 4], [4, 4], [1, 0], [2, 3]], 1, 3, 65], [0, 6, 2, 5, 'W+15.5']], [[['W..BWW', 'BBW..W', '..WB..', '....WB', 'WWWWW.', 'WWB...'], [[0, 5], [4, 5]], 2, 2, 55], [0, 1, 3, 2, 'W+5.5']]], [[[['..BW', '..BW', '.WBW', '.WBW', '..BW'], [[0, 3], [4, 2], [3, 0]], 0, 0, 60], [0, 0, 1, 1, 'W+6.0']], [[['.BW.', '.BW.', '.BW.', '.BW.', '.BWB', '.BWB', 'WBW.'], [[4, 1], [4, 1]], 0, 2, 0], [0, 0, 0, 3, 'W+3.0']], [[['W.BW...', '.WBW...', '..BW..B', '..BW...', '.WBWB..', '..BW...'], [[4, 4], [4, 0]], 3, 1, 55], [0, 0, 3, 2, 'W+4.5']], [[['WBW.B..', '.BW.B..', '.BWBB..', 'WBW....', '.BW.B..', '.BW.B..', 'WBW....'], [[2, 2], [6, 2], [2, 2]], 0, 1, 5], [0, 0, 2, 1, 'B+0.5']], [[['..BW', '.WBW', '..BW', '..BW', '..BW', '..BW'], [[1, 3], [3, 3], [1, 3]], 4, 1, 55], [0, 0, 6, 1, 'W+0.5']], [[['.....BW', '.....BW', '.....BW', '.W...BW', '.....BW'], [[3, 5], [1, 5], [3, 6], [3, 5]], 0, 3, 5], [0, 0, 1, 5, 'W+4.5']], [[['..B..', '..B..', 'BBBBB', 'WWWWW', '..W..'], [[4, 2]], 4, 3, 55], [8, 5, 5, 3, 'W+0.5']], [[['..W.W', 'B.BB.', 'BBB..'], [[0, 4], [2, 0]], 1, 1, 65], [1, 0, 2, 2, 'W+5.5']]], [[[['W..BWB', '...BW.', '...BW.', '...BWB'], [[0, 5]], 4, 0, 5], [0, 0, 4, 1, 'B+2.5']], [[['W...BW', '....BW', '....BW', '....BW', '....BW'], [[0, 0], [0, 4]], 0, 0, 5], [0, 0, 1, 1, 'W+0.5']], [[['..BWB', '..BWB', 'W.BW.', '..BW.', '..BW.'], [], 2, 4, 55], [0, 0, 2, 4, 'W+7.5']], [[['.BW..', 'WBWB.', '.BW..', 'WBW..', '.BW..'], [[2, 1], [3, 1]], 2, 2, 0], [0, 0, 2, 4, 'W+2.0']], [[['..BW...', '..BWB..', '.WBW...', '..BW.B.', 'W.BW...', '..BW...', '..BWBB.'], [[6, 2]], 2, 0, 65], [0, 0, 2, 1, 'W+5.5']], [[['.BW..', '.BW..', '.BW..', '.BW..', '.BWB.', '.BW..', 'WBW..'], [[0, 2], [0, 2]], 0, 2, 0], [0, 0, 1, 2, 'W+1.0']], [[['BBBB', 'B..B', 'B..B', 'BBBB'], [[2, 0], [1, 3], [2, 0]], 0, 4, 5], [6, 0, 0, 6, 'W+0.5']], [[['WWW', 'W.W', 'WWW'], [[0, 1], [2, 2]], 1, 3, 65], [0, 3, 3, 3, 'W+9.5']]], [[[['...BWB.', '...BW..', '...BW..', '...BW..', '...BW..'], [[1, 4], [2, 4], [4, 3]], 2, 1, 5], [0, 0, 4, 2, 'B+1.5']], [[['...BWBB', 'W..BW..', '..WBW..', '...BW..', '...BW.B', '...BWB.'], [[3, 4]], 2, 4, 5], [1, 0, 3, 4, 'W+0.5']], [[['.BW...', '.BWB..', '.BW...', '.BW...', '.BW...', '.BW...', '.BW.BB'], [[1, 1], [1, 1], [2, 4]], 4, 1, 60], [0, 0, 4, 2, 'W+4.0']], [[['...BW', '...BW', 'W..BW', '...BW', '.W.BW', '...BW', 'W..BW'], [], 1, 1, 0], [0, 0, 1, 1, 'Jigo']], [[['....BW.', 'W..WBW.', 'W...BW.', '..W.BW.', '....BW.', '....BW.'], [[3, 4], [4, 4], [1, 0], [2, 3]], 1, 3, 65], [0, 6, 2, 5, 'W+15.5']], [[['....', '....', '....', '....'], [], 4, 0, 60], [0, 0, 4, 0, 'W+2.0']], [[['..W', '.W.', 'W..'], [[0, 2], [2, 0]], 3, 2, 60], [0, 8, 5, 2, 'W+11.0']], [[['BBB', 'BWB', 'BBB'], [[1, 1]], 0, 0, 0], [1, 0, 1, 0, 'B+2.0']]]]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check("territory score case %d" % i, 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 fixture	Actual	Expected	Outcome
territory score case 0	`[0, 0, 5, 5, 'W+6.0']`	`[0, 0, 5, 5, 'W+6.0']`	Passed
territory score case 1	`[0, 0, 5, 1, 'W+2.5']`	`[0, 0, 5, 1, 'W+2.5']`	Passed
territory score case 2	`[0, 0, 1, 2, 'W+1.0']`	`[0, 0, 1, 2, 'W+1.0']`	Passed
territory score case 3	`[0, 0, 4, 2, 'B+2.0']`	`[0, 0, 4, 2, 'B+2.0']`	Passed
territory score case 4	`[0, 0, 0, 1, 'W+7.5']`	`[0, 0, 0, 1, 'W+7.5']`	Passed
territory score case 5	`[0, 0, 3, 3, 'W+0.5']`	`[0, 0, 3, 3, 'W+0.5']`	Passed
territory score case 6	`[0, 14, 3, 4, 'W+15.0']`	`[0, 14, 3, 4, 'W+15.0']`	Passed
territory score case 7	`[0, 0, 2, 0, 'W+4.5']`	`[1, 0, 2, 0, 'W+3.5']`	Failed

SHA-256 / a33a81f7be30984d4cbe747737d33239b63e52432448127bb58b1337514a4fad

3 / The verified repair

Exit 0

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

N = 1
observations = []
def solve(x):
    board, dead, capb, capw, komi = x
    g = [list(row) for row in board]
    pb = capb
    pw = capw
    for r, c in dead:
        if g[r][c] == 'B':
            pw += 1
        elif g[r][c] == 'W':
            pb += 1
        g[r][c] = '.'
    n = len(g)
    m = len(g[0])
    tb = 0
    tw = 0
    seen = set()
    for r in range(n):
        for c in range(m):
            if g[r][c] != '.' or (r, c) in seen:
                continue
            stack = [(r, c)]
            seen.add((r, c))
            size = 0
            owners = set()
            while stack:
                i, j = stack.pop()
                size += 1
                for p, q in ((i + 1, j), (i - 1, j), (i, j + 1), (i, j - 1)):
                    if 0 <= p < n and 0 <= q < m:
                        if g[p][q] == '.':
                            if (p, q) not in seen:
                                seen.add((p, q))
                                stack.append((p, q))
                        else:
                            owners.add(g[p][q])
            if owners == {'B'}:
                tb += size
            elif owners == {'W'}:
                tw += size
    sb = (tb + pb) * 10
    sw = (tw + pw) * 10 + komi
    if sb > sw:
        res = 'B+%d.%d' % ((sb - sw) // 10, (sb - sw) % 10)
    elif sw > sb:
        res = 'W+%d.%d' % ((sw - sb) // 10, (sw - sb) % 10)
    else:
        res = 'Jigo'
    return [tb, tw, pb, pw, res]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[[[['.WBW..', '..BW.B', '..BW..', '..BW..', '..BWB.', 'WWBW..'], [[4, 4], [0, 1], [4, 4]], 4, 4, 60], [0, 0, 5, 5, 'W+6.0']], [[['..WBW', '...BW', '...BW', 'W..BW'], [[0, 3], [3, 4], [3, 0]], 3, 0, 65], [0, 0, 5, 1, 'W+2.5']], [[['..BW.', '..BW.', '..BW.', '..BWB', '..BW.', '..BW.'], [[3, 2], [3, 2]], 1, 1, 0], [0, 0, 1, 2, 'W+1.0']], [[['.BW.B..', '.BW....', '.BW....', '.BW.B..', '.BW....', '.BW.B..', '.BW....'], [[4, 2], [2, 1], [6, 1]], 3, 0, 0], [0, 0, 4, 2, 'B+2.0']], [[['.....BW', '....WBW', '.W...BW', '..W..BW', '...W.BW'], [[4, 5]], 0, 0, 65], [0, 0, 0, 1, 'W+7.5']], [[['W..BW.', '..WBW.', 'W..BW.', '...BW.', '...BW.', '..WBW.'], [[1, 2], [5, 2], [0, 4]], 0, 3, 5], [0, 0, 3, 3, 'W+0.5']], [[['W.BW..', 'W.BW..', '..BW..', '.WBW..', '..BW..', '..BW..', '..BW..'], [[3, 2]], 3, 3, 0], [0, 14, 3, 4, 'W+15.0']], [[['BBB', 'BWB', 'BBB'], [[1, 1], [1, 1]], 1, 0, 65], [1, 0, 2, 0, 'W+3.5']]], [[[['W.BW..', '..BW..', '..BW..', '.WBW.B', 'W.BW..', '..BW..', '.WBW..'], [[1, 2], [3, 2], [5, 0]], 2, 0, 55], [0, 0, 2, 2, 'W+5.5']], [[['....BW.', '....BW.', '.W..BW.', '...WBW.', '...WBWB', '....BW.'], [[5, 1]], 4, 3, 55], [0, 0, 4, 3, 'W+4.5']], [[['...BW..', '...BWB.', '...BW..', '...BW..', '...BW..'], [[0, 3], [0, 3], [4, 2]], 0, 1, 5], [0, 0, 0, 2, 'W+2.5']], [[['..BW', '.WBW', '..BW', '..BW'], [[3, 2], [0, 3], [3, 2]], 0, 4, 60], [0, 0, 1, 5, 'W+10.0']], [[['....BWB', '....BW.', '....BW.', '....BWB'], [[2, 5]], 4, 1, 0], [16, 0, 5, 1, 'B+20.0']], [[['.BW.', '.BW.', '.BW.', '.BW.'], [[3, 1]], 1, 1, 60], [0, 4, 1, 2, 'W+11.0']], [[['....BW.', 'W..WBW.', 'W...BW.', '..W.BW.', '....BW.', '....BW.'], [[3, 4], [4, 4], [1, 0], [2, 3]], 1, 3, 65], [0, 6, 2, 5, 'W+15.5']], [[['W..BWW', 'BBW..W', '..WB..', '....WB', 'WWWWW.', 'WWB...'], [[0, 5], [4, 5]], 2, 2, 55], [0, 1, 3, 2, 'W+5.5']]], [[[['..BW', '..BW', '.WBW', '.WBW', '..BW'], [[0, 3], [4, 2], [3, 0]], 0, 0, 60], [0, 0, 1, 1, 'W+6.0']], [[['.BW.', '.BW.', '.BW.', '.BW.', '.BWB', '.BWB', 'WBW.'], [[4, 1], [4, 1]], 0, 2, 0], [0, 0, 0, 3, 'W+3.0']], [[['W.BW...', '.WBW...', '..BW..B', '..BW...', '.WBWB..', '..BW...'], [[4, 4], [4, 0]], 3, 1, 55], [0, 0, 3, 2, 'W+4.5']], [[['WBW.B..', '.BW.B..', '.BWBB..', 'WBW....', '.BW.B..', '.BW.B..', 'WBW....'], [[2, 2], [6, 2], [2, 2]], 0, 1, 5], [0, 0, 2, 1, 'B+0.5']], [[['..BW', '.WBW', '..BW', '..BW', '..BW', '..BW'], [[1, 3], [3, 3], [1, 3]], 4, 1, 55], [0, 0, 6, 1, 'W+0.5']], [[['.....BW', '.....BW', '.....BW', '.W...BW', '.....BW'], [[3, 5], [1, 5], [3, 6], [3, 5]], 0, 3, 5], [0, 0, 1, 5, 'W+4.5']], [[['..B..', '..B..', 'BBBBB', 'WWWWW', '..W..'], [[4, 2]], 4, 3, 55], [8, 5, 5, 3, 'W+0.5']], [[['..W.W', 'B.BB.', 'BBB..'], [[0, 4], [2, 0]], 1, 1, 65], [1, 0, 2, 2, 'W+5.5']]], [[[['W..BWB', '...BW.', '...BW.', '...BWB'], [[0, 5]], 4, 0, 5], [0, 0, 4, 1, 'B+2.5']], [[['W...BW', '....BW', '....BW', '....BW', '....BW'], [[0, 0], [0, 4]], 0, 0, 5], [0, 0, 1, 1, 'W+0.5']], [[['..BWB', '..BWB', 'W.BW.', '..BW.', '..BW.'], [], 2, 4, 55], [0, 0, 2, 4, 'W+7.5']], [[['.BW..', 'WBWB.', '.BW..', 'WBW..', '.BW..'], [[2, 1], [3, 1]], 2, 2, 0], [0, 0, 2, 4, 'W+2.0']], [[['..BW...', '..BWB..', '.WBW...', '..BW.B.', 'W.BW...', '..BW...', '..BWBB.'], [[6, 2]], 2, 0, 65], [0, 0, 2, 1, 'W+5.5']], [[['.BW..', '.BW..', '.BW..', '.BW..', '.BWB.', '.BW..', 'WBW..'], [[0, 2], [0, 2]], 0, 2, 0], [0, 0, 1, 2, 'W+1.0']], [[['BBBB', 'B..B', 'B..B', 'BBBB'], [[2, 0], [1, 3], [2, 0]], 0, 4, 5], [6, 0, 0, 6, 'W+0.5']], [[['WWW', 'W.W', 'WWW'], [[0, 1], [2, 2]], 1, 3, 65], [0, 3, 3, 3, 'W+9.5']]], [[[['...BWB.', '...BW..', '...BW..', '...BW..', '...BW..'], [[1, 4], [2, 4], [4, 3]], 2, 1, 5], [0, 0, 4, 2, 'B+1.5']], [[['...BWBB', 'W..BW..', '..WBW..', '...BW..', '...BW.B', '...BWB.'], [[3, 4]], 2, 4, 5], [1, 0, 3, 4, 'W+0.5']], [[['.BW...', '.BWB..', '.BW...', '.BW...', '.BW...', '.BW...', '.BW.BB'], [[1, 1], [1, 1], [2, 4]], 4, 1, 60], [0, 0, 4, 2, 'W+4.0']], [[['...BW', '...BW', 'W..BW', '...BW', '.W.BW', '...BW', 'W..BW'], [], 1, 1, 0], [0, 0, 1, 1, 'Jigo']], [[['....BW.', 'W..WBW.', 'W...BW.', '..W.BW.', '....BW.', '....BW.'], [[3, 4], [4, 4], [1, 0], [2, 3]], 1, 3, 65], [0, 6, 2, 5, 'W+15.5']], [[['....', '....', '....', '....'], [], 4, 0, 60], [0, 0, 4, 0, 'W+2.0']], [[['..W', '.W.', 'W..'], [[0, 2], [2, 0]], 3, 2, 60], [0, 8, 5, 2, 'W+11.0']], [[['BBB', 'BWB', 'BBB'], [[1, 1]], 0, 0, 0], [1, 0, 1, 0, 'B+2.0']]]]
for i, (args, expected) in enumerate(fixtures[N-1]):
    check("territory score case %d" % i, 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 fixture	Actual	Expected	Outcome
territory score case 0	`[0, 0, 5, 5, 'W+6.0']`	`[0, 0, 5, 5, 'W+6.0']`	Passed
territory score case 1	`[0, 0, 5, 1, 'W+2.5']`	`[0, 0, 5, 1, 'W+2.5']`	Passed
territory score case 2	`[0, 0, 1, 2, 'W+1.0']`	`[0, 0, 1, 2, 'W+1.0']`	Passed
territory score case 3	`[0, 0, 4, 2, 'B+2.0']`	`[0, 0, 4, 2, 'B+2.0']`	Passed
territory score case 4	`[0, 0, 0, 1, 'W+7.5']`	`[0, 0, 0, 1, 'W+7.5']`	Passed
territory score case 5	`[0, 0, 3, 3, 'W+0.5']`	`[0, 0, 3, 3, 'W+0.5']`	Passed
territory score case 6	`[0, 14, 3, 4, 'W+15.0']`	`[0, 14, 3, 4, 'W+15.0']`	Passed
territory score case 7	`[1, 0, 2, 0, 'W+3.5']`	`[1, 0, 2, 0, 'W+3.5']`	Passed

SHA-256 / 3baf5f13e3172801f8b5b30955d199da494ef97e518fc5f28de62250526f9d3f

Verification & scope

Small rectangular toy boards given as strings of B, W and dot; a bounded teaching model of one scoring or bookkeeping rule, not a complete rules engine or server implementation. 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 2026-09-29T14:50:16.074360+00:00.

Case digest / 58109f9cb48e1d2ad459941377a2d6eb2c4219d4d993682768b38b846fb77839