FAILURE MAP
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FA-92096 / PLC ladder logic scan cycles / Open access

Sequencer advances every scan while enable is held · case 01

Holding the step input races through the whole sequence.

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

ROOT CAUSE

The advance condition tests the enable level instead of its rising edge.

VERIFIED REPAIR

Advance only when enable is true and was false on the previous scan.

Unsuccessful approach: Stopping at the last element instead of edge-detecting still cannot wrap.

Case contract

Sequencer output (SQO). words is the sequencer file whose element 0 is the home step; position starts at 0. On each rising edge of enable the position advances; past the last element it wraps to 1 (not 0). Each advance writes dest = (dest AND NOT mask) OR (word AND mask) in 16 bits. A reset input returns position to 0 without writing dest and has priority over a coincident advance; the enable edge memory is always updated. steps is a list of [enable, reset]; return [position, dest] per scan.

Why this case matters

Ladder programs are executed as repeated scans; each defect here changes what a rung, timer, counter or data-table instruction reports on a particular scan, which is how commissioning and field faults are actually observed.

1 / The failure

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

N = 1
observations = []
def solve(words, mask, start_dest, steps):
    pos = 0
    dest = start_dest
    prev = False
    length = len(words) - 1
    out = []
    for en, res in steps:
        en = bool(en)
        if res:
            pos = 0
        elif en:
            pos += 1
            if pos > length:
                pos = 1
            dest = (dest & ~mask & 0xFFFF) | (words[pos] & mask)
        prev = en
        out.append([pos, dest])
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['regression: wrap past last step',
   [[0, 17, 34],
    255,
    43776,
    [[True, False], [False, False], [True, False], [False, False], [True, False], [True, False]]],
   [[1, 43793], [1, 43793], [2, 43810], [2, 43810], [1, 43793], [1, 43793]]],
  ['regression: scenario 5',
   [[31779, 18767, 26849],
    3855,
    17424,
    [[True, False],
     [False, False],
     [False, False],
     [True, False],
     [False, False],
     [False, False],
     [False, False],
     [False, False],
     [False, False],
     [False, False],
     [True, False],
     [True, False]]],
   [[1, 18719],
    [1, 18719],
    [1, 18719],
    [2, 18449],
    [2, 18449],
    [2, 18449],
    [2, 18449],
    [2, 18449],
    [2, 18449],
    [2, 18449],
    [1, 18719],
    [1, 18719]]],
  ['control: two element file',
   [[5, 9], 65535, 0, [[True, False], [False, False], [True, False], [False, False], [True, False]]],
   [[1, 9], [1, 9], [1, 9], [1, 9], [1, 9]]],
  ['control: reset while enabled',
   [[0, 3, 12], 15, 65520, [[True, False], [True, True], [False, False], [True, False]]],
   [[1, 65523], [0, 65523], [0, 65523], [1, 65523]]],
  ['control: reset with advance',
   [[0, 256, 512], 65280, 170, [[False, False], [True, True], [False, False], [True, False]]],
   [[0, 170], [0, 170], [0, 170], [1, 426]]],
  ['regression: scenario 1',
   [[26918, 50611, 8879, 59828],
    65535,
    52597,
    [[False, False],
     [False, False],
     [False, False],
     [True, True],
     [False, False],
     [False, False],
     [False, False],
     [True, False],
     [True, False],
     [False, False]]],
   [[0, 52597],
    [0, 52597],
    [0, 52597],
    [0, 52597],
    [0, 52597],
    [0, 52597],
    [0, 52597],
    [1, 50611],
    [1, 50611],
    [1, 50611]]],
  ['control: scenario 2',
   [[42968, 29173, 43546],
    255,
    5794,
    [[True, False],
     [False, False],
     [False, False],
     [False, False],
     [True, False],
     [False, False],
     [False, False],
     [False, False],
     [True, True],
     [False, False]]],
   [[1, 5877],
    [1, 5877],
    [1, 5877],
    [1, 5877],
    [2, 5658],
    [2, 5658],
    [2, 5658],
    [2, 5658],
    [0, 5658],
    [0, 5658]]],
  ['regression: scenario 3',
   [[16785, 47110, 21847, 45361],
    61440,
    41889,
    [[True, False],
     [True, False],
     [True, False],
     [True, False],
     [True, False],
     [False, False],
     [False, False]]],
   [[1, 45985], [1, 45985], [1, 45985], [1, 45985], [1, 45985], [1, 45985], [1, 45985]]]],
 [['regression: scenario 1',
   [[8488, 43469, 38296, 4034],
    255,
    44563,
    [[False, False],
     [True, False],
     [True, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [True, False]]],
   [[0, 44563],
    [1, 44749],
    [1, 44749],
    [1, 44749],
    [1, 44749],
    [2, 44696],
    [2, 44696],
    [3, 44738],
    [3, 44738],
    [1, 44749],
    [1, 44749],
    [2, 44696]]],
  ['regression: scenario 21',
   [[35992, 43053, 59445],
    65535,
    52164,
    [[False, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [True, False],
     [True, False],
     [True, False],
     [True, False],
     [False, True],
     [False, False]]],
   [[0, 52164],
    [1, 43053],
    [1, 43053],
    [2, 59445],
    [2, 59445],
    [1, 43053],
    [1, 43053],
    [2, 59445],
    [2, 59445],
    [2, 59445],
    [2, 59445],
    [0, 59445],
    [0, 59445]]],
  ['regression: wrap past last step',
   [[0, 17, 34],
    255,
    43776,
    [[True, False], [False, False], [True, False], [False, False], [True, False], [True, False]]],
   [[1, 43793], [1, 43793], [2, 43810], [2, 43810], [1, 43793], [1, 43793]]],
  ['control: two element file',
   [[5, 9], 65535, 0, [[True, False], [False, False], [True, False], [False, False], [True, False]]],
   [[1, 9], [1, 9], [1, 9], [1, 9], [1, 9]]],
  ['control: reset while enabled',
   [[0, 3, 12], 15, 65520, [[True, False], [True, True], [False, False], [True, False]]],
   [[1, 65523], [0, 65523], [0, 65523], [1, 65523]]],
  ['control: reset with advance',
   [[0, 256, 512], 65280, 170, [[False, False], [True, True], [False, False], [True, False]]],
   [[0, 170], [0, 170], [0, 170], [1, 426]]],
  ['regression: scenario 2',
   [[43079, 20640, 23622, 26553],
    255,
    15109,
    [[False, False],
     [False, False],
     [True, False],
     [True, False],
     [False, False],
     [False, False],
     [True, False],
     [True, False],
     [False, False],
     [False, False],
     [True, False],
     [False, True]]],
   [[0, 15109],
    [0, 15109],
    [1, 15264],
    [1, 15264],
    [1, 15264],
    [1, 15264],
    [2, 15174],
    [2, 15174],
    [2, 15174],
    [2, 15174],
    [3, 15289],
    [0, 15289]]],
  ['regression: scenario 3',
   [[16618, 36272, 41924, 55813],
    3855,
    48911,
    [[True, False],
     [True, False],
     [True, False],
     [False, False],
     [False, False],
     [True, False],
     [False, False]]],
   [[1, 48384], [1, 48384], [1, 48384], [1, 48384], [1, 48384], [2, 45828], [2, 45828]]]],
 [['regression: scenario 3',
   [[45414, 65173, 31151, 4829],
    3855,
    46402,
    [[False, True],
     [False, False],
     [True, True],
     [False, False],
     [False, False],
     [False, False],
     [True, False],
     [True, False],
     [True, False]]],
   [[0, 46402],
    [0, 46402],
    [0, 46402],
    [0, 46402],
    [0, 46402],
    [0, 46402],
    [1, 48709],
    [1, 48709],
    [1, 48709]]],
  ['regression: scenario 6',
   [[53426, 5627, 11199, 28564],
    3855,
    26531,
    [[True, False],
     [True, False],
     [False, False],
     [True, False],
     [True, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [False, False],
     [True, False],
     [False, False],
     [False, False],
     [False, False]]],
   [[1, 26027],
    [1, 26027],
    [1, 26027],
    [2, 27567],
    [2, 27567],
    [2, 27567],
    [2, 27567],
    [3, 28580],
    [3, 28580],
    [3, 28580],
    [1, 26027],
    [1, 26027],
    [1, 26027],
    [1, 26027]]],
  ['regression: wrap past last step',
   [[0, 17, 34],
    255,
    43776,
    [[True, False], [False, False], [True, False], [False, False], [True, False], [True, False]]],
   [[1, 43793], [1, 43793], [2, 43810], [2, 43810], [1, 43793], [1, 43793]]],
  ['control: two element file',
   [[5, 9], 65535, 0, [[True, False], [False, False], [True, False], [False, False], [True, False]]],
   [[1, 9], [1, 9], [1, 9], [1, 9], [1, 9]]],
  ['control: reset while enabled',
   [[0, 3, 12], 15, 65520, [[True, False], [True, True], [False, False], [True, False]]],
   [[1, 65523], [0, 65523], [0, 65523], [1, 65523]]],
  ['control: reset with advance',
   [[0, 256, 512], 65280, 170, [[False, False], [True, True], [False, False], [True, False]]],
   [[0, 170], [0, 170], [0, 170], [1, 426]]],
  ['control: scenario 1',
   [[38610, 2229],
    65535,
    14704,
    [[False, False],
     [False, False],
     [False, False],
     [False, False],
     [False, False],
     [True, False],
     [True, False],
     [False, True],
     [False, False]]],
   [[0, 14704], [0, 14704], [0, 14704], [0, 14704], [0, 14704], [1, 2229], [1, 2229], [0, 2229], [0, 2229]]],
  ['regression: scenario 2',
   [[36741, 30504],
    65535,
    26589,
    [[True, False],
     [False, False],
     [False, False],
     [True, False],
     [True, False],
     [False, False],
     [False, False],
     [False, False],
     [True, True],
     [True, False],
     [False, False]]],
   [[1, 30504],
    [1, 30504],
    [1, 30504],
    [1, 30504],
    [1, 30504],
    [1, 30504],
    [1, 30504],
    [1, 30504],
    [0, 30504],
    [0, 30504],
    [0, 30504]]]],
 [['regression: scenario 6',
   [[41259, 64194, 24167],
    255,
    50548,
    [[True, False],
     [False, False],
     [True, True],
     [False, False],
     [True, False],
     [True, False],
     [False, False]]],
   [[1, 50626], [1, 50626], [0, 50626], [0, 50626], [1, 50626], [1, 50626], [1, 50626]]],
  ['regression: scenario 34',
   [[14407, 35134, 61773],
    65535,
    32422,
    [[True, False],
     [False, False],
     [True, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [True, False],
     [True, False],
     [False, False],
     [False, False],
     [False, False],
     [False, False]]],
   [[1, 35134],
    [1, 35134],
    [2, 61773],
    [2, 61773],
    [2, 61773],
    [1, 35134],
    [1, 35134],
    [2, 61773],
    [2, 61773],
    [2, 61773],
    [2, 61773],
    [2, 61773],
    [2, 61773]]],
  ['regression: wrap past last step',
   [[0, 17, 34],
    255,
    43776,
    [[True, False], [False, False], [True, False], [False, False], [True, False], [True, False]]],
   [[1, 43793], [1, 43793], [2, 43810], [2, 43810], [1, 43793], [1, 43793]]],
  ['control: two element file',
   [[5, 9], 65535, 0, [[True, False], [False, False], [True, False], [False, False], [True, False]]],
   [[1, 9], [1, 9], [1, 9], [1, 9], [1, 9]]],
  ['control: reset while enabled',
   [[0, 3, 12], 15, 65520, [[True, False], [True, True], [False, False], [True, False]]],
   [[1, 65523], [0, 65523], [0, 65523], [1, 65523]]],
  ['control: reset with advance',
   [[0, 256, 512], 65280, 170, [[False, False], [True, True], [False, False], [True, False]]],
   [[0, 170], [0, 170], [0, 170], [1, 426]]],
  ['control: scenario 1',
   [[61786, 58708],
    255,
    45362,
    [[False, False],
     [False, False],
     [False, False],
     [True, False],
     [False, False],
     [False, False],
     [True, False]]],
   [[0, 45362], [0, 45362], [0, 45362], [1, 45396], [1, 45396], [1, 45396], [1, 45396]]],
  ['control: scenario 2',
   [[57902, 51779],
    61440,
    26811,
    [[True, False],
     [True, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [False, False],
     [True, False]]],
   [[1, 51387], [1, 51387], [1, 51387], [1, 51387], [1, 51387], [1, 51387], [1, 51387], [1, 51387]]]],
 [['regression: scenario 6',
   [[49875, 17863, 34135],
    3855,
    57202,
    [[False, False], [True, False], [True, False], [True, True], [False, False], [False, False]]],
   [[0, 57202], [1, 54647], [1, 54647], [0, 54647], [0, 54647], [0, 54647]]],
  ['regression: scenario 46',
   [[23503, 30684, 5429],
    61440,
    58681,
    [[True, False],
     [True, False],
     [False, False],
     [False, False],
     [True, False],
     [True, False],
     [True, False],
     [False, False],
     [False, False],
     [False, False],
     [False, False],
     [False, False],
     [True, False]]],
   [[1, 30009],
    [1, 30009],
    [1, 30009],
    [1, 30009],
    [2, 5433],
    [2, 5433],
    [2, 5433],
    [2, 5433],
    [2, 5433],
    [2, 5433],
    [2, 5433],
    [2, 5433],
    [1, 30009]]],
  ['regression: wrap past last step',
   [[0, 17, 34],
    255,
    43776,
    [[True, False], [False, False], [True, False], [False, False], [True, False], [True, False]]],
   [[1, 43793], [1, 43793], [2, 43810], [2, 43810], [1, 43793], [1, 43793]]],
  ['control: two element file',
   [[5, 9], 65535, 0, [[True, False], [False, False], [True, False], [False, False], [True, False]]],
   [[1, 9], [1, 9], [1, 9], [1, 9], [1, 9]]],
  ['control: reset while enabled',
   [[0, 3, 12], 15, 65520, [[True, False], [True, True], [False, False], [True, False]]],
   [[1, 65523], [0, 65523], [0, 65523], [1, 65523]]],
  ['control: reset with advance',
   [[0, 256, 512], 65280, 170, [[False, False], [True, True], [False, False], [True, False]]],
   [[0, 170], [0, 170], [0, 170], [1, 426]]],
  ['control: scenario 1',
   [[39974, 26951],
    3855,
    4546,
    [[False, False],
     [False, False],
     [True, False],
     [False, False],
     [True, False],
     [True, False],
     [False, False],
     [False, False],
     [True, False],
     [True, True]]],
   [[0, 4546],
    [0, 4546],
    [1, 6599],
    [1, 6599],
    [1, 6599],
    [1, 6599],
    [1, 6599],
    [1, 6599],
    [1, 6599],
    [0, 6599]]],
  ['regression: scenario 2',
   [[43067, 57880, 6921, 33106, 51712],
    255,
    13830,
    [[True, False],
     [False, False],
     [False, False],
     [True, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [True, True],
     [True, True],
     [False, False],
     [True, False],
     [False, False]]],
   [[1, 13848],
    [1, 13848],
    [1, 13848],
    [2, 13833],
    [2, 13833],
    [2, 13833],
    [3, 13906],
    [3, 13906],
    [0, 13906],
    [0, 13906],
    [0, 13906],
    [1, 13848],
    [1, 13848]]]]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
regression: wrap past last step[[1, 43793], [1, 43793], [2, 43810], [2, 43810], [1, 43793], [2, 43810]][[1, 43793], [1, 43793], [2, 43810], [2, 43810], [1, 43793], [1, 43793]]Failed
regression: scenario 5[[1, 18719], [1, 18719], [1, 18719], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [1, 18719], [2, 18449]][[1, 18719], [1, 18719], [1, 18719], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [1, 18719], [1, 18719]]Failed
control: two element file[[1, 9], [1, 9], [1, 9], [1, 9], [1, 9]][[1, 9], [1, 9], [1, 9], [1, 9], [1, 9]]Passed
control: reset while enabled[[1, 65523], [0, 65523], [0, 65523], [1, 65523]][[1, 65523], [0, 65523], [0, 65523], [1, 65523]]Passed
control: reset with advance[[0, 170], [0, 170], [0, 170], [1, 426]][[0, 170], [0, 170], [0, 170], [1, 426]]Passed
regression: scenario 1[[0, 52597], [0, 52597], [0, 52597], [0, 52597], [0, 52597], [0, 52597], [0, 52597], [1, 50611], [2, 8879], [2, 8879]][[0, 52597], [0, 52597], [0, 52597], [0, 52597], [0, 52597], [0, 52597], [0, 52597], [1, 50611], [1, 50611], [1, 50611]]Failed
control: scenario 2[[1, 5877], [1, 5877], [1, 5877], [1, 5877], [2, 5658], [2, 5658], [2, 5658], [2, 5658], [0, 5658], [0, 5658]][[1, 5877], [1, 5877], [1, 5877], [1, 5877], [2, 5658], [2, 5658], [2, 5658], [2, 5658], [0, 5658], [0, 5658]]Passed
regression: scenario 3[[1, 45985], [2, 21409], [3, 45985], [1, 45985], [2, 21409], [2, 21409], [2, 21409]][[1, 45985], [1, 45985], [1, 45985], [1, 45985], [1, 45985], [1, 45985], [1, 45985]]Failed

SHA-256 / e82a3d0c0abbf84fda12e06da96cebc43d479ed1e9ca056dda64e0311ad23b12

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(words, mask, start_dest, steps):
    pos = 0
    dest = start_dest
    prev = False
    length = len(words) - 1
    out = []
    for en, res in steps:
        en = bool(en)
        if res:
            pos = 0
        elif en and not prev and pos < length:
            pos += 1
            if pos > length:
                pos = 1
            dest = (dest & ~mask & 0xFFFF) | (words[pos] & mask)
        prev = en
        out.append([pos, dest])
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['regression: wrap past last step',
   [[0, 17, 34],
    255,
    43776,
    [[True, False], [False, False], [True, False], [False, False], [True, False], [True, False]]],
   [[1, 43793], [1, 43793], [2, 43810], [2, 43810], [1, 43793], [1, 43793]]],
  ['regression: scenario 5',
   [[31779, 18767, 26849],
    3855,
    17424,
    [[True, False],
     [False, False],
     [False, False],
     [True, False],
     [False, False],
     [False, False],
     [False, False],
     [False, False],
     [False, False],
     [False, False],
     [True, False],
     [True, False]]],
   [[1, 18719],
    [1, 18719],
    [1, 18719],
    [2, 18449],
    [2, 18449],
    [2, 18449],
    [2, 18449],
    [2, 18449],
    [2, 18449],
    [2, 18449],
    [1, 18719],
    [1, 18719]]],
  ['control: two element file',
   [[5, 9], 65535, 0, [[True, False], [False, False], [True, False], [False, False], [True, False]]],
   [[1, 9], [1, 9], [1, 9], [1, 9], [1, 9]]],
  ['control: reset while enabled',
   [[0, 3, 12], 15, 65520, [[True, False], [True, True], [False, False], [True, False]]],
   [[1, 65523], [0, 65523], [0, 65523], [1, 65523]]],
  ['control: reset with advance',
   [[0, 256, 512], 65280, 170, [[False, False], [True, True], [False, False], [True, False]]],
   [[0, 170], [0, 170], [0, 170], [1, 426]]],
  ['regression: scenario 1',
   [[26918, 50611, 8879, 59828],
    65535,
    52597,
    [[False, False],
     [False, False],
     [False, False],
     [True, True],
     [False, False],
     [False, False],
     [False, False],
     [True, False],
     [True, False],
     [False, False]]],
   [[0, 52597],
    [0, 52597],
    [0, 52597],
    [0, 52597],
    [0, 52597],
    [0, 52597],
    [0, 52597],
    [1, 50611],
    [1, 50611],
    [1, 50611]]],
  ['control: scenario 2',
   [[42968, 29173, 43546],
    255,
    5794,
    [[True, False],
     [False, False],
     [False, False],
     [False, False],
     [True, False],
     [False, False],
     [False, False],
     [False, False],
     [True, True],
     [False, False]]],
   [[1, 5877],
    [1, 5877],
    [1, 5877],
    [1, 5877],
    [2, 5658],
    [2, 5658],
    [2, 5658],
    [2, 5658],
    [0, 5658],
    [0, 5658]]],
  ['regression: scenario 3',
   [[16785, 47110, 21847, 45361],
    61440,
    41889,
    [[True, False],
     [True, False],
     [True, False],
     [True, False],
     [True, False],
     [False, False],
     [False, False]]],
   [[1, 45985], [1, 45985], [1, 45985], [1, 45985], [1, 45985], [1, 45985], [1, 45985]]]],
 [['regression: scenario 1',
   [[8488, 43469, 38296, 4034],
    255,
    44563,
    [[False, False],
     [True, False],
     [True, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [True, False]]],
   [[0, 44563],
    [1, 44749],
    [1, 44749],
    [1, 44749],
    [1, 44749],
    [2, 44696],
    [2, 44696],
    [3, 44738],
    [3, 44738],
    [1, 44749],
    [1, 44749],
    [2, 44696]]],
  ['regression: scenario 21',
   [[35992, 43053, 59445],
    65535,
    52164,
    [[False, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [True, False],
     [True, False],
     [True, False],
     [True, False],
     [False, True],
     [False, False]]],
   [[0, 52164],
    [1, 43053],
    [1, 43053],
    [2, 59445],
    [2, 59445],
    [1, 43053],
    [1, 43053],
    [2, 59445],
    [2, 59445],
    [2, 59445],
    [2, 59445],
    [0, 59445],
    [0, 59445]]],
  ['regression: wrap past last step',
   [[0, 17, 34],
    255,
    43776,
    [[True, False], [False, False], [True, False], [False, False], [True, False], [True, False]]],
   [[1, 43793], [1, 43793], [2, 43810], [2, 43810], [1, 43793], [1, 43793]]],
  ['control: two element file',
   [[5, 9], 65535, 0, [[True, False], [False, False], [True, False], [False, False], [True, False]]],
   [[1, 9], [1, 9], [1, 9], [1, 9], [1, 9]]],
  ['control: reset while enabled',
   [[0, 3, 12], 15, 65520, [[True, False], [True, True], [False, False], [True, False]]],
   [[1, 65523], [0, 65523], [0, 65523], [1, 65523]]],
  ['control: reset with advance',
   [[0, 256, 512], 65280, 170, [[False, False], [True, True], [False, False], [True, False]]],
   [[0, 170], [0, 170], [0, 170], [1, 426]]],
  ['regression: scenario 2',
   [[43079, 20640, 23622, 26553],
    255,
    15109,
    [[False, False],
     [False, False],
     [True, False],
     [True, False],
     [False, False],
     [False, False],
     [True, False],
     [True, False],
     [False, False],
     [False, False],
     [True, False],
     [False, True]]],
   [[0, 15109],
    [0, 15109],
    [1, 15264],
    [1, 15264],
    [1, 15264],
    [1, 15264],
    [2, 15174],
    [2, 15174],
    [2, 15174],
    [2, 15174],
    [3, 15289],
    [0, 15289]]],
  ['regression: scenario 3',
   [[16618, 36272, 41924, 55813],
    3855,
    48911,
    [[True, False],
     [True, False],
     [True, False],
     [False, False],
     [False, False],
     [True, False],
     [False, False]]],
   [[1, 48384], [1, 48384], [1, 48384], [1, 48384], [1, 48384], [2, 45828], [2, 45828]]]],
 [['regression: scenario 3',
   [[45414, 65173, 31151, 4829],
    3855,
    46402,
    [[False, True],
     [False, False],
     [True, True],
     [False, False],
     [False, False],
     [False, False],
     [True, False],
     [True, False],
     [True, False]]],
   [[0, 46402],
    [0, 46402],
    [0, 46402],
    [0, 46402],
    [0, 46402],
    [0, 46402],
    [1, 48709],
    [1, 48709],
    [1, 48709]]],
  ['regression: scenario 6',
   [[53426, 5627, 11199, 28564],
    3855,
    26531,
    [[True, False],
     [True, False],
     [False, False],
     [True, False],
     [True, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [False, False],
     [True, False],
     [False, False],
     [False, False],
     [False, False]]],
   [[1, 26027],
    [1, 26027],
    [1, 26027],
    [2, 27567],
    [2, 27567],
    [2, 27567],
    [2, 27567],
    [3, 28580],
    [3, 28580],
    [3, 28580],
    [1, 26027],
    [1, 26027],
    [1, 26027],
    [1, 26027]]],
  ['regression: wrap past last step',
   [[0, 17, 34],
    255,
    43776,
    [[True, False], [False, False], [True, False], [False, False], [True, False], [True, False]]],
   [[1, 43793], [1, 43793], [2, 43810], [2, 43810], [1, 43793], [1, 43793]]],
  ['control: two element file',
   [[5, 9], 65535, 0, [[True, False], [False, False], [True, False], [False, False], [True, False]]],
   [[1, 9], [1, 9], [1, 9], [1, 9], [1, 9]]],
  ['control: reset while enabled',
   [[0, 3, 12], 15, 65520, [[True, False], [True, True], [False, False], [True, False]]],
   [[1, 65523], [0, 65523], [0, 65523], [1, 65523]]],
  ['control: reset with advance',
   [[0, 256, 512], 65280, 170, [[False, False], [True, True], [False, False], [True, False]]],
   [[0, 170], [0, 170], [0, 170], [1, 426]]],
  ['control: scenario 1',
   [[38610, 2229],
    65535,
    14704,
    [[False, False],
     [False, False],
     [False, False],
     [False, False],
     [False, False],
     [True, False],
     [True, False],
     [False, True],
     [False, False]]],
   [[0, 14704], [0, 14704], [0, 14704], [0, 14704], [0, 14704], [1, 2229], [1, 2229], [0, 2229], [0, 2229]]],
  ['regression: scenario 2',
   [[36741, 30504],
    65535,
    26589,
    [[True, False],
     [False, False],
     [False, False],
     [True, False],
     [True, False],
     [False, False],
     [False, False],
     [False, False],
     [True, True],
     [True, False],
     [False, False]]],
   [[1, 30504],
    [1, 30504],
    [1, 30504],
    [1, 30504],
    [1, 30504],
    [1, 30504],
    [1, 30504],
    [1, 30504],
    [0, 30504],
    [0, 30504],
    [0, 30504]]]],
 [['regression: scenario 6',
   [[41259, 64194, 24167],
    255,
    50548,
    [[True, False],
     [False, False],
     [True, True],
     [False, False],
     [True, False],
     [True, False],
     [False, False]]],
   [[1, 50626], [1, 50626], [0, 50626], [0, 50626], [1, 50626], [1, 50626], [1, 50626]]],
  ['regression: scenario 34',
   [[14407, 35134, 61773],
    65535,
    32422,
    [[True, False],
     [False, False],
     [True, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [True, False],
     [True, False],
     [False, False],
     [False, False],
     [False, False],
     [False, False]]],
   [[1, 35134],
    [1, 35134],
    [2, 61773],
    [2, 61773],
    [2, 61773],
    [1, 35134],
    [1, 35134],
    [2, 61773],
    [2, 61773],
    [2, 61773],
    [2, 61773],
    [2, 61773],
    [2, 61773]]],
  ['regression: wrap past last step',
   [[0, 17, 34],
    255,
    43776,
    [[True, False], [False, False], [True, False], [False, False], [True, False], [True, False]]],
   [[1, 43793], [1, 43793], [2, 43810], [2, 43810], [1, 43793], [1, 43793]]],
  ['control: two element file',
   [[5, 9], 65535, 0, [[True, False], [False, False], [True, False], [False, False], [True, False]]],
   [[1, 9], [1, 9], [1, 9], [1, 9], [1, 9]]],
  ['control: reset while enabled',
   [[0, 3, 12], 15, 65520, [[True, False], [True, True], [False, False], [True, False]]],
   [[1, 65523], [0, 65523], [0, 65523], [1, 65523]]],
  ['control: reset with advance',
   [[0, 256, 512], 65280, 170, [[False, False], [True, True], [False, False], [True, False]]],
   [[0, 170], [0, 170], [0, 170], [1, 426]]],
  ['control: scenario 1',
   [[61786, 58708],
    255,
    45362,
    [[False, False],
     [False, False],
     [False, False],
     [True, False],
     [False, False],
     [False, False],
     [True, False]]],
   [[0, 45362], [0, 45362], [0, 45362], [1, 45396], [1, 45396], [1, 45396], [1, 45396]]],
  ['control: scenario 2',
   [[57902, 51779],
    61440,
    26811,
    [[True, False],
     [True, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [False, False],
     [True, False]]],
   [[1, 51387], [1, 51387], [1, 51387], [1, 51387], [1, 51387], [1, 51387], [1, 51387], [1, 51387]]]],
 [['regression: scenario 6',
   [[49875, 17863, 34135],
    3855,
    57202,
    [[False, False], [True, False], [True, False], [True, True], [False, False], [False, False]]],
   [[0, 57202], [1, 54647], [1, 54647], [0, 54647], [0, 54647], [0, 54647]]],
  ['regression: scenario 46',
   [[23503, 30684, 5429],
    61440,
    58681,
    [[True, False],
     [True, False],
     [False, False],
     [False, False],
     [True, False],
     [True, False],
     [True, False],
     [False, False],
     [False, False],
     [False, False],
     [False, False],
     [False, False],
     [True, False]]],
   [[1, 30009],
    [1, 30009],
    [1, 30009],
    [1, 30009],
    [2, 5433],
    [2, 5433],
    [2, 5433],
    [2, 5433],
    [2, 5433],
    [2, 5433],
    [2, 5433],
    [2, 5433],
    [1, 30009]]],
  ['regression: wrap past last step',
   [[0, 17, 34],
    255,
    43776,
    [[True, False], [False, False], [True, False], [False, False], [True, False], [True, False]]],
   [[1, 43793], [1, 43793], [2, 43810], [2, 43810], [1, 43793], [1, 43793]]],
  ['control: two element file',
   [[5, 9], 65535, 0, [[True, False], [False, False], [True, False], [False, False], [True, False]]],
   [[1, 9], [1, 9], [1, 9], [1, 9], [1, 9]]],
  ['control: reset while enabled',
   [[0, 3, 12], 15, 65520, [[True, False], [True, True], [False, False], [True, False]]],
   [[1, 65523], [0, 65523], [0, 65523], [1, 65523]]],
  ['control: reset with advance',
   [[0, 256, 512], 65280, 170, [[False, False], [True, True], [False, False], [True, False]]],
   [[0, 170], [0, 170], [0, 170], [1, 426]]],
  ['control: scenario 1',
   [[39974, 26951],
    3855,
    4546,
    [[False, False],
     [False, False],
     [True, False],
     [False, False],
     [True, False],
     [True, False],
     [False, False],
     [False, False],
     [True, False],
     [True, True]]],
   [[0, 4546],
    [0, 4546],
    [1, 6599],
    [1, 6599],
    [1, 6599],
    [1, 6599],
    [1, 6599],
    [1, 6599],
    [1, 6599],
    [0, 6599]]],
  ['regression: scenario 2',
   [[43067, 57880, 6921, 33106, 51712],
    255,
    13830,
    [[True, False],
     [False, False],
     [False, False],
     [True, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [True, True],
     [True, True],
     [False, False],
     [True, False],
     [False, False]]],
   [[1, 13848],
    [1, 13848],
    [1, 13848],
    [2, 13833],
    [2, 13833],
    [2, 13833],
    [3, 13906],
    [3, 13906],
    [0, 13906],
    [0, 13906],
    [0, 13906],
    [1, 13848],
    [1, 13848]]]]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
regression: wrap past last step[[1, 43793], [1, 43793], [2, 43810], [2, 43810], [2, 43810], [2, 43810]][[1, 43793], [1, 43793], [2, 43810], [2, 43810], [1, 43793], [1, 43793]]Failed
regression: scenario 5[[1, 18719], [1, 18719], [1, 18719], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [2, 18449]][[1, 18719], [1, 18719], [1, 18719], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [1, 18719], [1, 18719]]Failed
control: two element file[[1, 9], [1, 9], [1, 9], [1, 9], [1, 9]][[1, 9], [1, 9], [1, 9], [1, 9], [1, 9]]Passed
control: reset while enabled[[1, 65523], [0, 65523], [0, 65523], [1, 65523]][[1, 65523], [0, 65523], [0, 65523], [1, 65523]]Passed
control: reset with advance[[0, 170], [0, 170], [0, 170], [1, 426]][[0, 170], [0, 170], [0, 170], [1, 426]]Passed
regression: scenario 1[[0, 52597], [0, 52597], [0, 52597], [0, 52597], [0, 52597], [0, 52597], [0, 52597], [1, 50611], [1, 50611], [1, 50611]][[0, 52597], [0, 52597], [0, 52597], [0, 52597], [0, 52597], [0, 52597], [0, 52597], [1, 50611], [1, 50611], [1, 50611]]Passed
control: scenario 2[[1, 5877], [1, 5877], [1, 5877], [1, 5877], [2, 5658], [2, 5658], [2, 5658], [2, 5658], [0, 5658], [0, 5658]][[1, 5877], [1, 5877], [1, 5877], [1, 5877], [2, 5658], [2, 5658], [2, 5658], [2, 5658], [0, 5658], [0, 5658]]Passed
regression: scenario 3[[1, 45985], [1, 45985], [1, 45985], [1, 45985], [1, 45985], [1, 45985], [1, 45985]][[1, 45985], [1, 45985], [1, 45985], [1, 45985], [1, 45985], [1, 45985], [1, 45985]]Passed

SHA-256 / 565404a6ea7389b592fe8405f2ead375a83772be171d10bffe6ceb69afe4e99d

3 / The verified repair

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

N = 1
observations = []
def solve(words, mask, start_dest, steps):
    pos = 0
    dest = start_dest
    prev = False
    length = len(words) - 1
    out = []
    for en, res in steps:
        en = bool(en)
        if res:
            pos = 0
        elif en and not prev:
            pos += 1
            if pos > length:
                pos = 1
            dest = (dest & ~mask & 0xFFFF) | (words[pos] & mask)
        prev = en
        out.append([pos, dest])
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['regression: wrap past last step',
   [[0, 17, 34],
    255,
    43776,
    [[True, False], [False, False], [True, False], [False, False], [True, False], [True, False]]],
   [[1, 43793], [1, 43793], [2, 43810], [2, 43810], [1, 43793], [1, 43793]]],
  ['regression: scenario 5',
   [[31779, 18767, 26849],
    3855,
    17424,
    [[True, False],
     [False, False],
     [False, False],
     [True, False],
     [False, False],
     [False, False],
     [False, False],
     [False, False],
     [False, False],
     [False, False],
     [True, False],
     [True, False]]],
   [[1, 18719],
    [1, 18719],
    [1, 18719],
    [2, 18449],
    [2, 18449],
    [2, 18449],
    [2, 18449],
    [2, 18449],
    [2, 18449],
    [2, 18449],
    [1, 18719],
    [1, 18719]]],
  ['control: two element file',
   [[5, 9], 65535, 0, [[True, False], [False, False], [True, False], [False, False], [True, False]]],
   [[1, 9], [1, 9], [1, 9], [1, 9], [1, 9]]],
  ['control: reset while enabled',
   [[0, 3, 12], 15, 65520, [[True, False], [True, True], [False, False], [True, False]]],
   [[1, 65523], [0, 65523], [0, 65523], [1, 65523]]],
  ['control: reset with advance',
   [[0, 256, 512], 65280, 170, [[False, False], [True, True], [False, False], [True, False]]],
   [[0, 170], [0, 170], [0, 170], [1, 426]]],
  ['regression: scenario 1',
   [[26918, 50611, 8879, 59828],
    65535,
    52597,
    [[False, False],
     [False, False],
     [False, False],
     [True, True],
     [False, False],
     [False, False],
     [False, False],
     [True, False],
     [True, False],
     [False, False]]],
   [[0, 52597],
    [0, 52597],
    [0, 52597],
    [0, 52597],
    [0, 52597],
    [0, 52597],
    [0, 52597],
    [1, 50611],
    [1, 50611],
    [1, 50611]]],
  ['control: scenario 2',
   [[42968, 29173, 43546],
    255,
    5794,
    [[True, False],
     [False, False],
     [False, False],
     [False, False],
     [True, False],
     [False, False],
     [False, False],
     [False, False],
     [True, True],
     [False, False]]],
   [[1, 5877],
    [1, 5877],
    [1, 5877],
    [1, 5877],
    [2, 5658],
    [2, 5658],
    [2, 5658],
    [2, 5658],
    [0, 5658],
    [0, 5658]]],
  ['regression: scenario 3',
   [[16785, 47110, 21847, 45361],
    61440,
    41889,
    [[True, False],
     [True, False],
     [True, False],
     [True, False],
     [True, False],
     [False, False],
     [False, False]]],
   [[1, 45985], [1, 45985], [1, 45985], [1, 45985], [1, 45985], [1, 45985], [1, 45985]]]],
 [['regression: scenario 1',
   [[8488, 43469, 38296, 4034],
    255,
    44563,
    [[False, False],
     [True, False],
     [True, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [True, False]]],
   [[0, 44563],
    [1, 44749],
    [1, 44749],
    [1, 44749],
    [1, 44749],
    [2, 44696],
    [2, 44696],
    [3, 44738],
    [3, 44738],
    [1, 44749],
    [1, 44749],
    [2, 44696]]],
  ['regression: scenario 21',
   [[35992, 43053, 59445],
    65535,
    52164,
    [[False, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [True, False],
     [True, False],
     [True, False],
     [True, False],
     [False, True],
     [False, False]]],
   [[0, 52164],
    [1, 43053],
    [1, 43053],
    [2, 59445],
    [2, 59445],
    [1, 43053],
    [1, 43053],
    [2, 59445],
    [2, 59445],
    [2, 59445],
    [2, 59445],
    [0, 59445],
    [0, 59445]]],
  ['regression: wrap past last step',
   [[0, 17, 34],
    255,
    43776,
    [[True, False], [False, False], [True, False], [False, False], [True, False], [True, False]]],
   [[1, 43793], [1, 43793], [2, 43810], [2, 43810], [1, 43793], [1, 43793]]],
  ['control: two element file',
   [[5, 9], 65535, 0, [[True, False], [False, False], [True, False], [False, False], [True, False]]],
   [[1, 9], [1, 9], [1, 9], [1, 9], [1, 9]]],
  ['control: reset while enabled',
   [[0, 3, 12], 15, 65520, [[True, False], [True, True], [False, False], [True, False]]],
   [[1, 65523], [0, 65523], [0, 65523], [1, 65523]]],
  ['control: reset with advance',
   [[0, 256, 512], 65280, 170, [[False, False], [True, True], [False, False], [True, False]]],
   [[0, 170], [0, 170], [0, 170], [1, 426]]],
  ['regression: scenario 2',
   [[43079, 20640, 23622, 26553],
    255,
    15109,
    [[False, False],
     [False, False],
     [True, False],
     [True, False],
     [False, False],
     [False, False],
     [True, False],
     [True, False],
     [False, False],
     [False, False],
     [True, False],
     [False, True]]],
   [[0, 15109],
    [0, 15109],
    [1, 15264],
    [1, 15264],
    [1, 15264],
    [1, 15264],
    [2, 15174],
    [2, 15174],
    [2, 15174],
    [2, 15174],
    [3, 15289],
    [0, 15289]]],
  ['regression: scenario 3',
   [[16618, 36272, 41924, 55813],
    3855,
    48911,
    [[True, False],
     [True, False],
     [True, False],
     [False, False],
     [False, False],
     [True, False],
     [False, False]]],
   [[1, 48384], [1, 48384], [1, 48384], [1, 48384], [1, 48384], [2, 45828], [2, 45828]]]],
 [['regression: scenario 3',
   [[45414, 65173, 31151, 4829],
    3855,
    46402,
    [[False, True],
     [False, False],
     [True, True],
     [False, False],
     [False, False],
     [False, False],
     [True, False],
     [True, False],
     [True, False]]],
   [[0, 46402],
    [0, 46402],
    [0, 46402],
    [0, 46402],
    [0, 46402],
    [0, 46402],
    [1, 48709],
    [1, 48709],
    [1, 48709]]],
  ['regression: scenario 6',
   [[53426, 5627, 11199, 28564],
    3855,
    26531,
    [[True, False],
     [True, False],
     [False, False],
     [True, False],
     [True, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [False, False],
     [True, False],
     [False, False],
     [False, False],
     [False, False]]],
   [[1, 26027],
    [1, 26027],
    [1, 26027],
    [2, 27567],
    [2, 27567],
    [2, 27567],
    [2, 27567],
    [3, 28580],
    [3, 28580],
    [3, 28580],
    [1, 26027],
    [1, 26027],
    [1, 26027],
    [1, 26027]]],
  ['regression: wrap past last step',
   [[0, 17, 34],
    255,
    43776,
    [[True, False], [False, False], [True, False], [False, False], [True, False], [True, False]]],
   [[1, 43793], [1, 43793], [2, 43810], [2, 43810], [1, 43793], [1, 43793]]],
  ['control: two element file',
   [[5, 9], 65535, 0, [[True, False], [False, False], [True, False], [False, False], [True, False]]],
   [[1, 9], [1, 9], [1, 9], [1, 9], [1, 9]]],
  ['control: reset while enabled',
   [[0, 3, 12], 15, 65520, [[True, False], [True, True], [False, False], [True, False]]],
   [[1, 65523], [0, 65523], [0, 65523], [1, 65523]]],
  ['control: reset with advance',
   [[0, 256, 512], 65280, 170, [[False, False], [True, True], [False, False], [True, False]]],
   [[0, 170], [0, 170], [0, 170], [1, 426]]],
  ['control: scenario 1',
   [[38610, 2229],
    65535,
    14704,
    [[False, False],
     [False, False],
     [False, False],
     [False, False],
     [False, False],
     [True, False],
     [True, False],
     [False, True],
     [False, False]]],
   [[0, 14704], [0, 14704], [0, 14704], [0, 14704], [0, 14704], [1, 2229], [1, 2229], [0, 2229], [0, 2229]]],
  ['regression: scenario 2',
   [[36741, 30504],
    65535,
    26589,
    [[True, False],
     [False, False],
     [False, False],
     [True, False],
     [True, False],
     [False, False],
     [False, False],
     [False, False],
     [True, True],
     [True, False],
     [False, False]]],
   [[1, 30504],
    [1, 30504],
    [1, 30504],
    [1, 30504],
    [1, 30504],
    [1, 30504],
    [1, 30504],
    [1, 30504],
    [0, 30504],
    [0, 30504],
    [0, 30504]]]],
 [['regression: scenario 6',
   [[41259, 64194, 24167],
    255,
    50548,
    [[True, False],
     [False, False],
     [True, True],
     [False, False],
     [True, False],
     [True, False],
     [False, False]]],
   [[1, 50626], [1, 50626], [0, 50626], [0, 50626], [1, 50626], [1, 50626], [1, 50626]]],
  ['regression: scenario 34',
   [[14407, 35134, 61773],
    65535,
    32422,
    [[True, False],
     [False, False],
     [True, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [True, False],
     [True, False],
     [False, False],
     [False, False],
     [False, False],
     [False, False]]],
   [[1, 35134],
    [1, 35134],
    [2, 61773],
    [2, 61773],
    [2, 61773],
    [1, 35134],
    [1, 35134],
    [2, 61773],
    [2, 61773],
    [2, 61773],
    [2, 61773],
    [2, 61773],
    [2, 61773]]],
  ['regression: wrap past last step',
   [[0, 17, 34],
    255,
    43776,
    [[True, False], [False, False], [True, False], [False, False], [True, False], [True, False]]],
   [[1, 43793], [1, 43793], [2, 43810], [2, 43810], [1, 43793], [1, 43793]]],
  ['control: two element file',
   [[5, 9], 65535, 0, [[True, False], [False, False], [True, False], [False, False], [True, False]]],
   [[1, 9], [1, 9], [1, 9], [1, 9], [1, 9]]],
  ['control: reset while enabled',
   [[0, 3, 12], 15, 65520, [[True, False], [True, True], [False, False], [True, False]]],
   [[1, 65523], [0, 65523], [0, 65523], [1, 65523]]],
  ['control: reset with advance',
   [[0, 256, 512], 65280, 170, [[False, False], [True, True], [False, False], [True, False]]],
   [[0, 170], [0, 170], [0, 170], [1, 426]]],
  ['control: scenario 1',
   [[61786, 58708],
    255,
    45362,
    [[False, False],
     [False, False],
     [False, False],
     [True, False],
     [False, False],
     [False, False],
     [True, False]]],
   [[0, 45362], [0, 45362], [0, 45362], [1, 45396], [1, 45396], [1, 45396], [1, 45396]]],
  ['control: scenario 2',
   [[57902, 51779],
    61440,
    26811,
    [[True, False],
     [True, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [False, False],
     [True, False]]],
   [[1, 51387], [1, 51387], [1, 51387], [1, 51387], [1, 51387], [1, 51387], [1, 51387], [1, 51387]]]],
 [['regression: scenario 6',
   [[49875, 17863, 34135],
    3855,
    57202,
    [[False, False], [True, False], [True, False], [True, True], [False, False], [False, False]]],
   [[0, 57202], [1, 54647], [1, 54647], [0, 54647], [0, 54647], [0, 54647]]],
  ['regression: scenario 46',
   [[23503, 30684, 5429],
    61440,
    58681,
    [[True, False],
     [True, False],
     [False, False],
     [False, False],
     [True, False],
     [True, False],
     [True, False],
     [False, False],
     [False, False],
     [False, False],
     [False, False],
     [False, False],
     [True, False]]],
   [[1, 30009],
    [1, 30009],
    [1, 30009],
    [1, 30009],
    [2, 5433],
    [2, 5433],
    [2, 5433],
    [2, 5433],
    [2, 5433],
    [2, 5433],
    [2, 5433],
    [2, 5433],
    [1, 30009]]],
  ['regression: wrap past last step',
   [[0, 17, 34],
    255,
    43776,
    [[True, False], [False, False], [True, False], [False, False], [True, False], [True, False]]],
   [[1, 43793], [1, 43793], [2, 43810], [2, 43810], [1, 43793], [1, 43793]]],
  ['control: two element file',
   [[5, 9], 65535, 0, [[True, False], [False, False], [True, False], [False, False], [True, False]]],
   [[1, 9], [1, 9], [1, 9], [1, 9], [1, 9]]],
  ['control: reset while enabled',
   [[0, 3, 12], 15, 65520, [[True, False], [True, True], [False, False], [True, False]]],
   [[1, 65523], [0, 65523], [0, 65523], [1, 65523]]],
  ['control: reset with advance',
   [[0, 256, 512], 65280, 170, [[False, False], [True, True], [False, False], [True, False]]],
   [[0, 170], [0, 170], [0, 170], [1, 426]]],
  ['control: scenario 1',
   [[39974, 26951],
    3855,
    4546,
    [[False, False],
     [False, False],
     [True, False],
     [False, False],
     [True, False],
     [True, False],
     [False, False],
     [False, False],
     [True, False],
     [True, True]]],
   [[0, 4546],
    [0, 4546],
    [1, 6599],
    [1, 6599],
    [1, 6599],
    [1, 6599],
    [1, 6599],
    [1, 6599],
    [1, 6599],
    [0, 6599]]],
  ['regression: scenario 2',
   [[43067, 57880, 6921, 33106, 51712],
    255,
    13830,
    [[True, False],
     [False, False],
     [False, False],
     [True, False],
     [True, False],
     [False, False],
     [True, False],
     [False, False],
     [True, True],
     [True, True],
     [False, False],
     [True, False],
     [False, False]]],
   [[1, 13848],
    [1, 13848],
    [1, 13848],
    [2, 13833],
    [2, 13833],
    [2, 13833],
    [3, 13906],
    [3, 13906],
    [0, 13906],
    [0, 13906],
    [0, 13906],
    [1, 13848],
    [1, 13848]]]]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
regression: wrap past last step[[1, 43793], [1, 43793], [2, 43810], [2, 43810], [1, 43793], [1, 43793]][[1, 43793], [1, 43793], [2, 43810], [2, 43810], [1, 43793], [1, 43793]]Passed
regression: scenario 5[[1, 18719], [1, 18719], [1, 18719], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [1, 18719], [1, 18719]][[1, 18719], [1, 18719], [1, 18719], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [2, 18449], [1, 18719], [1, 18719]]Passed
control: two element file[[1, 9], [1, 9], [1, 9], [1, 9], [1, 9]][[1, 9], [1, 9], [1, 9], [1, 9], [1, 9]]Passed
control: reset while enabled[[1, 65523], [0, 65523], [0, 65523], [1, 65523]][[1, 65523], [0, 65523], [0, 65523], [1, 65523]]Passed
control: reset with advance[[0, 170], [0, 170], [0, 170], [1, 426]][[0, 170], [0, 170], [0, 170], [1, 426]]Passed
regression: scenario 1[[0, 52597], [0, 52597], [0, 52597], [0, 52597], [0, 52597], [0, 52597], [0, 52597], [1, 50611], [1, 50611], [1, 50611]][[0, 52597], [0, 52597], [0, 52597], [0, 52597], [0, 52597], [0, 52597], [0, 52597], [1, 50611], [1, 50611], [1, 50611]]Passed
control: scenario 2[[1, 5877], [1, 5877], [1, 5877], [1, 5877], [2, 5658], [2, 5658], [2, 5658], [2, 5658], [0, 5658], [0, 5658]][[1, 5877], [1, 5877], [1, 5877], [1, 5877], [2, 5658], [2, 5658], [2, 5658], [2, 5658], [0, 5658], [0, 5658]]Passed
regression: scenario 3[[1, 45985], [1, 45985], [1, 45985], [1, 45985], [1, 45985], [1, 45985], [1, 45985]][[1, 45985], [1, 45985], [1, 45985], [1, 45985], [1, 45985], [1, 45985], [1, 45985]]Passed

SHA-256 / ee784ba15fa24cf9319cc8ced7415a0bf54e387175ce7ea0807e7709d1464cc2

Verification & scope

A deterministic bounded teaching model of one PLC instruction or rung pattern evaluated scan by scan. The stated contract is a stipulated toy convention, not a claim of conformance to any vendor controller or IEC 61131-3 runtime. 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 2026-09-29T14:51:42.460102+00:00.

Case digest / bd1db501f1fe2c627dccadf5e4a0ca11417e2c0b1cfb61725e93b8269777c025