FAILURE MAP
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FA-91896 / PLC ladder logic scan cycles / Open access

RTO discards accumulated time when its rung goes false · case 01

A retentive timer loses its partial accumulation across a stop and restarts from zero.

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

ROOT CAUSE

The disabled-rung path clears ACC and DN as if the instruction were a TON.

VERIFIED REPAIR

Leave ACC and DN unchanged while the RTO rung is false.

Unsuccessful approach: Clearing only DN on a false rung still drops a completed timer that should stay done.

Case contract

Retentive timer (RTO) on rung 1 and its reset (RES) on a later rung, evaluated per scan; scans is a list of [enable, reset, elapsed_ms]. An enabled scan whose previous scan was also enabled adds the elapsed time (clamped at preset); DN sets when ACC >= preset while enabled. A disabled rung retains ACC and DN. Because RES is a later rung, a reset in a scan clears ACC and DN after the RTO has run; the enable edge memory is not touched by RES. Return [DN, ACC] 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(preset, scans):
    acc = 0
    dn = False
    prev = False
    out = []
    for en, res, dt in scans:
        en = bool(en)
        if en:
            if prev:
                acc = min(preset, acc + dt)
            if acc >= preset:
                dn = True
        else:
            acc = 0
            dn = False
        prev = en
        if res:
            acc = 0
            dn = False
        out.append([dn, acc])
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['regression: interrupted timing retained',
   [100,
    [[True, False, 30],
     [True, False, 40],
     [False, False, 40],
     [True, False, 40],
     [True, False, 40],
     [True, False, 40]]],
   [[False, 0], [False, 40], [False, 40], [False, 40], [False, 80], [True, 100]]],
  ['regression: reset done timer while disabled',
   [50, [[True, False, 30], [True, False, 60], [False, False, 10], [False, True, 10], [False, False, 10]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 0]]],
  ['control: reset while enabled',
   [100, [[True, False, 30], [True, False, 60], [True, True, 30], [True, False, 30], [True, False, 30]]],
   [[False, 0], [False, 60], [False, 0], [False, 30], [False, 60]]],
  ['control: reset done timer while enabled',
   [50,
    [[True, False, 30],
     [True, False, 60],
     [True, False, 10],
     [True, True, 10],
     [True, False, 25],
     [True, False, 25]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 25], [True, 50]]],
  ['regression: scenario 1',
   [100,
    [[False, False, 10],
     [False, False, 50],
     [False, False, 40],
     [True, True, 20],
     [False, False, 40],
     [True, False, 40],
     [True, False, 20],
     [False, False, 40]]],
   [[False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 20], [False, 20]]],
  ['control: scenario 2',
   [50,
    [[False, False, 30],
     [False, False, 30],
     [True, False, 50],
     [False, False, 50],
     [False, False, 10],
     [True, False, 30],
     [False, False, 50],
     [True, False, 30],
     [True, False, 40]]],
   [[False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 40]]],
  ['control: scenario 3',
   [100,
    [[False, False, 50],
     [False, False, 20],
     [True, False, 50],
     [True, False, 10],
     [True, False, 20],
     [True, False, 20],
     [True, False, 50],
     [True, False, 50],
     [True, True, 10],
     [True, False, 50]]],
   [[False, 0],
    [False, 0],
    [False, 0],
    [False, 10],
    [False, 30],
    [False, 50],
    [True, 100],
    [True, 100],
    [False, 0],
    [False, 50]]],
  ['regression: scenario 4',
   [100,
    [[True, False, 20],
     [True, False, 10],
     [False, False, 20],
     [True, False, 30],
     [False, False, 20],
     [False, False, 30]]],
   [[False, 0], [False, 10], [False, 10], [False, 10], [False, 10], [False, 10]]]],
 [['regression: reset done timer while disabled',
   [50, [[True, False, 30], [True, False, 60], [False, False, 10], [False, True, 10], [False, False, 10]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 0]]],
  ['regression: scenario 3',
   [50,
    [[True, True, 10],
     [True, False, 20],
     [True, False, 10],
     [True, False, 20],
     [True, False, 40],
     [True, False, 50],
     [True, False, 30],
     [False, False, 20],
     [True, False, 40],
     [False, True, 20]]],
   [[False, 0],
    [False, 20],
    [False, 30],
    [True, 50],
    [True, 50],
    [True, 50],
    [True, 50],
    [True, 50],
    [True, 50],
    [False, 0]]],
  ['regression: interrupted timing retained',
   [100,
    [[True, False, 30],
     [True, False, 40],
     [False, False, 40],
     [True, False, 40],
     [True, False, 40],
     [True, False, 40]]],
   [[False, 0], [False, 40], [False, 40], [False, 40], [False, 80], [True, 100]]],
  ['control: reset while enabled',
   [100, [[True, False, 30], [True, False, 60], [True, True, 30], [True, False, 30], [True, False, 30]]],
   [[False, 0], [False, 60], [False, 0], [False, 30], [False, 60]]],
  ['control: reset done timer while enabled',
   [50,
    [[True, False, 30],
     [True, False, 60],
     [True, False, 10],
     [True, True, 10],
     [True, False, 25],
     [True, False, 25]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 25], [True, 50]]],
  ['regression: scenario 1',
   [80,
    [[False, False, 10],
     [True, False, 30],
     [True, False, 10],
     [True, True, 40],
     [True, False, 50],
     [False, False, 40],
     [False, False, 50],
     [False, False, 40]]],
   [[False, 0], [False, 0], [False, 10], [False, 0], [False, 50], [False, 50], [False, 50], [False, 50]]],
  ['regression: scenario 2',
   [0,
    [[True, False, 10],
     [False, False, 30],
     [True, False, 20],
     [True, False, 30],
     [True, False, 50],
     [True, False, 50],
     [True, True, 20],
     [True, False, 20],
     [False, False, 40]]],
   [[True, 0], [True, 0], [True, 0], [True, 0], [True, 0], [True, 0], [False, 0], [True, 0], [True, 0]]],
  ['control: scenario 4',
   [80,
    [[False, False, 20],
     [False, False, 40],
     [True, False, 50],
     [True, False, 40],
     [True, True, 40],
     [False, False, 10],
     [True, False, 10],
     [True, False, 30],
     [True, False, 50],
     [True, False, 40],
     [False, True, 30]]],
   [[False, 0],
    [False, 0],
    [False, 0],
    [False, 40],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 30],
    [True, 80],
    [True, 80],
    [False, 0]]]],
 [['regression: scenario 1',
   [0,
    [[False, False, 40],
     [False, True, 30],
     [True, False, 10],
     [True, False, 30],
     [True, False, 20],
     [False, True, 30],
     [True, False, 40],
     [True, False, 30],
     [True, False, 30],
     [False, False, 20],
     [False, False, 10],
     [True, False, 30],
     [True, False, 50],
     [False, False, 10]]],
   [[False, 0],
    [False, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [False, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0]]],
  ['regression: scenario 5',
   [100,
    [[True, False, 10],
     [True, False, 40],
     [True, False, 20],
     [True, False, 10],
     [True, False, 30],
     [True, False, 50],
     [False, False, 50],
     [True, False, 30],
     [True, False, 40],
     [False, False, 30]]],
   [[False, 0],
    [False, 40],
    [False, 60],
    [False, 70],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100]]],
  ['regression: interrupted timing retained',
   [100,
    [[True, False, 30],
     [True, False, 40],
     [False, False, 40],
     [True, False, 40],
     [True, False, 40],
     [True, False, 40]]],
   [[False, 0], [False, 40], [False, 40], [False, 40], [False, 80], [True, 100]]],
  ['control: reset while enabled',
   [100, [[True, False, 30], [True, False, 60], [True, True, 30], [True, False, 30], [True, False, 30]]],
   [[False, 0], [False, 60], [False, 0], [False, 30], [False, 60]]],
  ['control: reset done timer while enabled',
   [50,
    [[True, False, 30],
     [True, False, 60],
     [True, False, 10],
     [True, True, 10],
     [True, False, 25],
     [True, False, 25]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 25], [True, 50]]],
  ['regression: reset done timer while disabled',
   [50, [[True, False, 30], [True, False, 60], [False, False, 10], [False, True, 10], [False, False, 10]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 0]]],
  ['regression: scenario 2',
   [50,
    [[True, False, 10],
     [True, False, 20],
     [True, False, 50],
     [True, False, 20],
     [True, False, 20],
     [False, False, 50],
     [False, False, 40],
     [False, True, 10],
     [False, False, 10]]],
   [[False, 0],
    [False, 20],
    [True, 50],
    [True, 50],
    [True, 50],
    [True, 50],
    [True, 50],
    [False, 0],
    [False, 0]]],
  ['regression: scenario 3',
   [150,
    [[True, False, 50],
     [True, False, 30],
     [False, False, 50],
     [False, False, 40],
     [False, False, 50],
     [False, False, 20]]],
   [[False, 0], [False, 30], [False, 30], [False, 30], [False, 30], [False, 30]]]],
 [['regression: scenario 2',
   [100,
    [[True, False, 20],
     [True, False, 30],
     [True, False, 10],
     [True, True, 10],
     [True, False, 10],
     [True, False, 20],
     [False, False, 50],
     [False, True, 40],
     [False, False, 30],
     [False, False, 40],
     [True, False, 10],
     [True, False, 50]]],
   [[False, 0],
    [False, 30],
    [False, 40],
    [False, 0],
    [False, 10],
    [False, 30],
    [False, 30],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 50]]],
  ['regression: scenario 11',
   [100,
    [[True, False, 20],
     [True, True, 30],
     [True, True, 20],
     [True, False, 50],
     [True, False, 50],
     [True, False, 30],
     [False, False, 40],
     [True, False, 50],
     [False, False, 40]]],
   [[False, 0],
    [False, 0],
    [False, 0],
    [False, 50],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100]]],
  ['regression: interrupted timing retained',
   [100,
    [[True, False, 30],
     [True, False, 40],
     [False, False, 40],
     [True, False, 40],
     [True, False, 40],
     [True, False, 40]]],
   [[False, 0], [False, 40], [False, 40], [False, 40], [False, 80], [True, 100]]],
  ['control: reset while enabled',
   [100, [[True, False, 30], [True, False, 60], [True, True, 30], [True, False, 30], [True, False, 30]]],
   [[False, 0], [False, 60], [False, 0], [False, 30], [False, 60]]],
  ['control: reset done timer while enabled',
   [50,
    [[True, False, 30],
     [True, False, 60],
     [True, False, 10],
     [True, True, 10],
     [True, False, 25],
     [True, False, 25]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 25], [True, 50]]],
  ['regression: reset done timer while disabled',
   [50, [[True, False, 30], [True, False, 60], [False, False, 10], [False, True, 10], [False, False, 10]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 0]]],
  ['regression: scenario 1',
   [0,
    [[False, False, 50],
     [False, False, 20],
     [False, False, 30],
     [True, True, 40],
     [False, True, 10],
     [True, False, 10],
     [False, False, 30]]],
   [[False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [True, 0], [True, 0]]],
  ['control: scenario 3',
   [100,
    [[False, False, 10],
     [True, False, 20],
     [True, False, 10],
     [True, True, 50],
     [True, False, 40],
     [True, False, 50],
     [False, True, 50],
     [False, False, 10],
     [True, False, 30]]],
   [[False, 0],
    [False, 0],
    [False, 10],
    [False, 0],
    [False, 40],
    [False, 90],
    [False, 0],
    [False, 0],
    [False, 0]]]],
 [['regression: scenario 5',
   [150,
    [[True, False, 50],
     [True, False, 30],
     [False, False, 40],
     [True, False, 50],
     [True, False, 40],
     [False, False, 50],
     [False, False, 20],
     [False, False, 50],
     [True, False, 40],
     [False, False, 40],
     [True, True, 10]]],
   [[False, 0],
    [False, 30],
    [False, 30],
    [False, 30],
    [False, 70],
    [False, 70],
    [False, 70],
    [False, 70],
    [False, 70],
    [False, 70],
    [False, 0]]],
  ['regression: scenario 13',
   [0,
    [[True, False, 10],
     [True, False, 50],
     [True, False, 50],
     [False, False, 30],
     [False, False, 20],
     [True, False, 10],
     [True, False, 50],
     [True, True, 50],
     [False, False, 10],
     [True, True, 30],
     [True, False, 40],
     [False, False, 20]]],
   [[True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [True, 0],
    [True, 0]]],
  ['regression: interrupted timing retained',
   [100,
    [[True, False, 30],
     [True, False, 40],
     [False, False, 40],
     [True, False, 40],
     [True, False, 40],
     [True, False, 40]]],
   [[False, 0], [False, 40], [False, 40], [False, 40], [False, 80], [True, 100]]],
  ['control: reset while enabled',
   [100, [[True, False, 30], [True, False, 60], [True, True, 30], [True, False, 30], [True, False, 30]]],
   [[False, 0], [False, 60], [False, 0], [False, 30], [False, 60]]],
  ['control: reset done timer while enabled',
   [50,
    [[True, False, 30],
     [True, False, 60],
     [True, False, 10],
     [True, True, 10],
     [True, False, 25],
     [True, False, 25]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 25], [True, 50]]],
  ['regression: reset done timer while disabled',
   [50, [[True, False, 30], [True, False, 60], [False, False, 10], [False, True, 10], [False, False, 10]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 0]]],
  ['regression: scenario 1',
   [0,
    [[True, False, 30],
     [True, False, 10],
     [True, False, 10],
     [True, False, 40],
     [False, False, 30],
     [False, False, 50],
     [False, True, 40],
     [True, False, 10],
     [True, False, 30],
     [True, False, 50],
     [False, False, 20],
     [False, False, 30],
     [False, False, 40],
     [False, False, 50]]],
   [[True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [False, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0]]],
  ['control: scenario 2',
   [50,
    [[True, True, 50],
     [False, False, 10],
     [True, False, 50],
     [False, True, 50],
     [False, False, 20],
     [True, False, 20]]],
   [[False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0]]]]]
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: interrupted timing retained[[False, 0], [False, 40], [False, 0], [False, 0], [False, 40], [False, 80]][[False, 0], [False, 40], [False, 40], [False, 40], [False, 80], [True, 100]]Failed
regression: reset done timer while disabled[[False, 0], [True, 50], [False, 0], [False, 0], [False, 0]][[False, 0], [True, 50], [True, 50], [False, 0], [False, 0]]Failed
control: reset while enabled[[False, 0], [False, 60], [False, 0], [False, 30], [False, 60]][[False, 0], [False, 60], [False, 0], [False, 30], [False, 60]]Passed
control: reset done timer while enabled[[False, 0], [True, 50], [True, 50], [False, 0], [False, 25], [True, 50]][[False, 0], [True, 50], [True, 50], [False, 0], [False, 25], [True, 50]]Passed
regression: scenario 1[[False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 20], [False, 0]][[False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 20], [False, 20]]Failed
control: scenario 2[[False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 40]][[False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 40]]Passed
control: scenario 3[[False, 0], [False, 0], [False, 0], [False, 10], [False, 30], [False, 50], [True, 100], [True, 100], [False, 0], [False, 50]][[False, 0], [False, 0], [False, 0], [False, 10], [False, 30], [False, 50], [True, 100], [True, 100], [False, 0], [False, 50]]Passed
regression: scenario 4[[False, 0], [False, 10], [False, 0], [False, 0], [False, 0], [False, 0]][[False, 0], [False, 10], [False, 10], [False, 10], [False, 10], [False, 10]]Failed

SHA-256 / 6790256e4ba40cb958245719b5ab349a3fb35448ffb54171200ba5f0ffe10cf4

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(preset, scans):
    acc = 0
    dn = False
    prev = False
    out = []
    for en, res, dt in scans:
        en = bool(en)
        if en:
            if prev:
                acc = min(preset, acc + dt)
            if acc >= preset:
                dn = True
        else:
            dn = False
        prev = en
        if res:
            acc = 0
            dn = False
        out.append([dn, acc])
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['regression: interrupted timing retained',
   [100,
    [[True, False, 30],
     [True, False, 40],
     [False, False, 40],
     [True, False, 40],
     [True, False, 40],
     [True, False, 40]]],
   [[False, 0], [False, 40], [False, 40], [False, 40], [False, 80], [True, 100]]],
  ['regression: reset done timer while disabled',
   [50, [[True, False, 30], [True, False, 60], [False, False, 10], [False, True, 10], [False, False, 10]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 0]]],
  ['control: reset while enabled',
   [100, [[True, False, 30], [True, False, 60], [True, True, 30], [True, False, 30], [True, False, 30]]],
   [[False, 0], [False, 60], [False, 0], [False, 30], [False, 60]]],
  ['control: reset done timer while enabled',
   [50,
    [[True, False, 30],
     [True, False, 60],
     [True, False, 10],
     [True, True, 10],
     [True, False, 25],
     [True, False, 25]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 25], [True, 50]]],
  ['regression: scenario 1',
   [100,
    [[False, False, 10],
     [False, False, 50],
     [False, False, 40],
     [True, True, 20],
     [False, False, 40],
     [True, False, 40],
     [True, False, 20],
     [False, False, 40]]],
   [[False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 20], [False, 20]]],
  ['control: scenario 2',
   [50,
    [[False, False, 30],
     [False, False, 30],
     [True, False, 50],
     [False, False, 50],
     [False, False, 10],
     [True, False, 30],
     [False, False, 50],
     [True, False, 30],
     [True, False, 40]]],
   [[False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 40]]],
  ['control: scenario 3',
   [100,
    [[False, False, 50],
     [False, False, 20],
     [True, False, 50],
     [True, False, 10],
     [True, False, 20],
     [True, False, 20],
     [True, False, 50],
     [True, False, 50],
     [True, True, 10],
     [True, False, 50]]],
   [[False, 0],
    [False, 0],
    [False, 0],
    [False, 10],
    [False, 30],
    [False, 50],
    [True, 100],
    [True, 100],
    [False, 0],
    [False, 50]]],
  ['regression: scenario 4',
   [100,
    [[True, False, 20],
     [True, False, 10],
     [False, False, 20],
     [True, False, 30],
     [False, False, 20],
     [False, False, 30]]],
   [[False, 0], [False, 10], [False, 10], [False, 10], [False, 10], [False, 10]]]],
 [['regression: reset done timer while disabled',
   [50, [[True, False, 30], [True, False, 60], [False, False, 10], [False, True, 10], [False, False, 10]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 0]]],
  ['regression: scenario 3',
   [50,
    [[True, True, 10],
     [True, False, 20],
     [True, False, 10],
     [True, False, 20],
     [True, False, 40],
     [True, False, 50],
     [True, False, 30],
     [False, False, 20],
     [True, False, 40],
     [False, True, 20]]],
   [[False, 0],
    [False, 20],
    [False, 30],
    [True, 50],
    [True, 50],
    [True, 50],
    [True, 50],
    [True, 50],
    [True, 50],
    [False, 0]]],
  ['regression: interrupted timing retained',
   [100,
    [[True, False, 30],
     [True, False, 40],
     [False, False, 40],
     [True, False, 40],
     [True, False, 40],
     [True, False, 40]]],
   [[False, 0], [False, 40], [False, 40], [False, 40], [False, 80], [True, 100]]],
  ['control: reset while enabled',
   [100, [[True, False, 30], [True, False, 60], [True, True, 30], [True, False, 30], [True, False, 30]]],
   [[False, 0], [False, 60], [False, 0], [False, 30], [False, 60]]],
  ['control: reset done timer while enabled',
   [50,
    [[True, False, 30],
     [True, False, 60],
     [True, False, 10],
     [True, True, 10],
     [True, False, 25],
     [True, False, 25]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 25], [True, 50]]],
  ['regression: scenario 1',
   [80,
    [[False, False, 10],
     [True, False, 30],
     [True, False, 10],
     [True, True, 40],
     [True, False, 50],
     [False, False, 40],
     [False, False, 50],
     [False, False, 40]]],
   [[False, 0], [False, 0], [False, 10], [False, 0], [False, 50], [False, 50], [False, 50], [False, 50]]],
  ['regression: scenario 2',
   [0,
    [[True, False, 10],
     [False, False, 30],
     [True, False, 20],
     [True, False, 30],
     [True, False, 50],
     [True, False, 50],
     [True, True, 20],
     [True, False, 20],
     [False, False, 40]]],
   [[True, 0], [True, 0], [True, 0], [True, 0], [True, 0], [True, 0], [False, 0], [True, 0], [True, 0]]],
  ['control: scenario 4',
   [80,
    [[False, False, 20],
     [False, False, 40],
     [True, False, 50],
     [True, False, 40],
     [True, True, 40],
     [False, False, 10],
     [True, False, 10],
     [True, False, 30],
     [True, False, 50],
     [True, False, 40],
     [False, True, 30]]],
   [[False, 0],
    [False, 0],
    [False, 0],
    [False, 40],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 30],
    [True, 80],
    [True, 80],
    [False, 0]]]],
 [['regression: scenario 1',
   [0,
    [[False, False, 40],
     [False, True, 30],
     [True, False, 10],
     [True, False, 30],
     [True, False, 20],
     [False, True, 30],
     [True, False, 40],
     [True, False, 30],
     [True, False, 30],
     [False, False, 20],
     [False, False, 10],
     [True, False, 30],
     [True, False, 50],
     [False, False, 10]]],
   [[False, 0],
    [False, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [False, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0]]],
  ['regression: scenario 5',
   [100,
    [[True, False, 10],
     [True, False, 40],
     [True, False, 20],
     [True, False, 10],
     [True, False, 30],
     [True, False, 50],
     [False, False, 50],
     [True, False, 30],
     [True, False, 40],
     [False, False, 30]]],
   [[False, 0],
    [False, 40],
    [False, 60],
    [False, 70],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100]]],
  ['regression: interrupted timing retained',
   [100,
    [[True, False, 30],
     [True, False, 40],
     [False, False, 40],
     [True, False, 40],
     [True, False, 40],
     [True, False, 40]]],
   [[False, 0], [False, 40], [False, 40], [False, 40], [False, 80], [True, 100]]],
  ['control: reset while enabled',
   [100, [[True, False, 30], [True, False, 60], [True, True, 30], [True, False, 30], [True, False, 30]]],
   [[False, 0], [False, 60], [False, 0], [False, 30], [False, 60]]],
  ['control: reset done timer while enabled',
   [50,
    [[True, False, 30],
     [True, False, 60],
     [True, False, 10],
     [True, True, 10],
     [True, False, 25],
     [True, False, 25]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 25], [True, 50]]],
  ['regression: reset done timer while disabled',
   [50, [[True, False, 30], [True, False, 60], [False, False, 10], [False, True, 10], [False, False, 10]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 0]]],
  ['regression: scenario 2',
   [50,
    [[True, False, 10],
     [True, False, 20],
     [True, False, 50],
     [True, False, 20],
     [True, False, 20],
     [False, False, 50],
     [False, False, 40],
     [False, True, 10],
     [False, False, 10]]],
   [[False, 0],
    [False, 20],
    [True, 50],
    [True, 50],
    [True, 50],
    [True, 50],
    [True, 50],
    [False, 0],
    [False, 0]]],
  ['regression: scenario 3',
   [150,
    [[True, False, 50],
     [True, False, 30],
     [False, False, 50],
     [False, False, 40],
     [False, False, 50],
     [False, False, 20]]],
   [[False, 0], [False, 30], [False, 30], [False, 30], [False, 30], [False, 30]]]],
 [['regression: scenario 2',
   [100,
    [[True, False, 20],
     [True, False, 30],
     [True, False, 10],
     [True, True, 10],
     [True, False, 10],
     [True, False, 20],
     [False, False, 50],
     [False, True, 40],
     [False, False, 30],
     [False, False, 40],
     [True, False, 10],
     [True, False, 50]]],
   [[False, 0],
    [False, 30],
    [False, 40],
    [False, 0],
    [False, 10],
    [False, 30],
    [False, 30],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 50]]],
  ['regression: scenario 11',
   [100,
    [[True, False, 20],
     [True, True, 30],
     [True, True, 20],
     [True, False, 50],
     [True, False, 50],
     [True, False, 30],
     [False, False, 40],
     [True, False, 50],
     [False, False, 40]]],
   [[False, 0],
    [False, 0],
    [False, 0],
    [False, 50],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100]]],
  ['regression: interrupted timing retained',
   [100,
    [[True, False, 30],
     [True, False, 40],
     [False, False, 40],
     [True, False, 40],
     [True, False, 40],
     [True, False, 40]]],
   [[False, 0], [False, 40], [False, 40], [False, 40], [False, 80], [True, 100]]],
  ['control: reset while enabled',
   [100, [[True, False, 30], [True, False, 60], [True, True, 30], [True, False, 30], [True, False, 30]]],
   [[False, 0], [False, 60], [False, 0], [False, 30], [False, 60]]],
  ['control: reset done timer while enabled',
   [50,
    [[True, False, 30],
     [True, False, 60],
     [True, False, 10],
     [True, True, 10],
     [True, False, 25],
     [True, False, 25]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 25], [True, 50]]],
  ['regression: reset done timer while disabled',
   [50, [[True, False, 30], [True, False, 60], [False, False, 10], [False, True, 10], [False, False, 10]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 0]]],
  ['regression: scenario 1',
   [0,
    [[False, False, 50],
     [False, False, 20],
     [False, False, 30],
     [True, True, 40],
     [False, True, 10],
     [True, False, 10],
     [False, False, 30]]],
   [[False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [True, 0], [True, 0]]],
  ['control: scenario 3',
   [100,
    [[False, False, 10],
     [True, False, 20],
     [True, False, 10],
     [True, True, 50],
     [True, False, 40],
     [True, False, 50],
     [False, True, 50],
     [False, False, 10],
     [True, False, 30]]],
   [[False, 0],
    [False, 0],
    [False, 10],
    [False, 0],
    [False, 40],
    [False, 90],
    [False, 0],
    [False, 0],
    [False, 0]]]],
 [['regression: scenario 5',
   [150,
    [[True, False, 50],
     [True, False, 30],
     [False, False, 40],
     [True, False, 50],
     [True, False, 40],
     [False, False, 50],
     [False, False, 20],
     [False, False, 50],
     [True, False, 40],
     [False, False, 40],
     [True, True, 10]]],
   [[False, 0],
    [False, 30],
    [False, 30],
    [False, 30],
    [False, 70],
    [False, 70],
    [False, 70],
    [False, 70],
    [False, 70],
    [False, 70],
    [False, 0]]],
  ['regression: scenario 13',
   [0,
    [[True, False, 10],
     [True, False, 50],
     [True, False, 50],
     [False, False, 30],
     [False, False, 20],
     [True, False, 10],
     [True, False, 50],
     [True, True, 50],
     [False, False, 10],
     [True, True, 30],
     [True, False, 40],
     [False, False, 20]]],
   [[True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [True, 0],
    [True, 0]]],
  ['regression: interrupted timing retained',
   [100,
    [[True, False, 30],
     [True, False, 40],
     [False, False, 40],
     [True, False, 40],
     [True, False, 40],
     [True, False, 40]]],
   [[False, 0], [False, 40], [False, 40], [False, 40], [False, 80], [True, 100]]],
  ['control: reset while enabled',
   [100, [[True, False, 30], [True, False, 60], [True, True, 30], [True, False, 30], [True, False, 30]]],
   [[False, 0], [False, 60], [False, 0], [False, 30], [False, 60]]],
  ['control: reset done timer while enabled',
   [50,
    [[True, False, 30],
     [True, False, 60],
     [True, False, 10],
     [True, True, 10],
     [True, False, 25],
     [True, False, 25]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 25], [True, 50]]],
  ['regression: reset done timer while disabled',
   [50, [[True, False, 30], [True, False, 60], [False, False, 10], [False, True, 10], [False, False, 10]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 0]]],
  ['regression: scenario 1',
   [0,
    [[True, False, 30],
     [True, False, 10],
     [True, False, 10],
     [True, False, 40],
     [False, False, 30],
     [False, False, 50],
     [False, True, 40],
     [True, False, 10],
     [True, False, 30],
     [True, False, 50],
     [False, False, 20],
     [False, False, 30],
     [False, False, 40],
     [False, False, 50]]],
   [[True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [False, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0]]],
  ['control: scenario 2',
   [50,
    [[True, True, 50],
     [False, False, 10],
     [True, False, 50],
     [False, True, 50],
     [False, False, 20],
     [True, False, 20]]],
   [[False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0]]]]]
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: interrupted timing retained[[False, 0], [False, 40], [False, 40], [False, 40], [False, 80], [True, 100]][[False, 0], [False, 40], [False, 40], [False, 40], [False, 80], [True, 100]]Passed
regression: reset done timer while disabled[[False, 0], [True, 50], [False, 50], [False, 0], [False, 0]][[False, 0], [True, 50], [True, 50], [False, 0], [False, 0]]Failed
control: reset while enabled[[False, 0], [False, 60], [False, 0], [False, 30], [False, 60]][[False, 0], [False, 60], [False, 0], [False, 30], [False, 60]]Passed
control: reset done timer while enabled[[False, 0], [True, 50], [True, 50], [False, 0], [False, 25], [True, 50]][[False, 0], [True, 50], [True, 50], [False, 0], [False, 25], [True, 50]]Passed
regression: scenario 1[[False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 20], [False, 20]][[False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 20], [False, 20]]Passed
control: scenario 2[[False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 40]][[False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 40]]Passed
control: scenario 3[[False, 0], [False, 0], [False, 0], [False, 10], [False, 30], [False, 50], [True, 100], [True, 100], [False, 0], [False, 50]][[False, 0], [False, 0], [False, 0], [False, 10], [False, 30], [False, 50], [True, 100], [True, 100], [False, 0], [False, 50]]Passed
regression: scenario 4[[False, 0], [False, 10], [False, 10], [False, 10], [False, 10], [False, 10]][[False, 0], [False, 10], [False, 10], [False, 10], [False, 10], [False, 10]]Passed

SHA-256 / 9dbc67cb13143d828ed07c2495744031e500b50c51acacf1c1c861d644ab92e8

3 / The verified repair

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

N = 1
observations = []
def solve(preset, scans):
    acc = 0
    dn = False
    prev = False
    out = []
    for en, res, dt in scans:
        en = bool(en)
        if en:
            if prev:
                acc = min(preset, acc + dt)
            if acc >= preset:
                dn = True
        prev = en
        if res:
            acc = 0
            dn = False
        out.append([dn, acc])
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['regression: interrupted timing retained',
   [100,
    [[True, False, 30],
     [True, False, 40],
     [False, False, 40],
     [True, False, 40],
     [True, False, 40],
     [True, False, 40]]],
   [[False, 0], [False, 40], [False, 40], [False, 40], [False, 80], [True, 100]]],
  ['regression: reset done timer while disabled',
   [50, [[True, False, 30], [True, False, 60], [False, False, 10], [False, True, 10], [False, False, 10]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 0]]],
  ['control: reset while enabled',
   [100, [[True, False, 30], [True, False, 60], [True, True, 30], [True, False, 30], [True, False, 30]]],
   [[False, 0], [False, 60], [False, 0], [False, 30], [False, 60]]],
  ['control: reset done timer while enabled',
   [50,
    [[True, False, 30],
     [True, False, 60],
     [True, False, 10],
     [True, True, 10],
     [True, False, 25],
     [True, False, 25]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 25], [True, 50]]],
  ['regression: scenario 1',
   [100,
    [[False, False, 10],
     [False, False, 50],
     [False, False, 40],
     [True, True, 20],
     [False, False, 40],
     [True, False, 40],
     [True, False, 20],
     [False, False, 40]]],
   [[False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 20], [False, 20]]],
  ['control: scenario 2',
   [50,
    [[False, False, 30],
     [False, False, 30],
     [True, False, 50],
     [False, False, 50],
     [False, False, 10],
     [True, False, 30],
     [False, False, 50],
     [True, False, 30],
     [True, False, 40]]],
   [[False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 40]]],
  ['control: scenario 3',
   [100,
    [[False, False, 50],
     [False, False, 20],
     [True, False, 50],
     [True, False, 10],
     [True, False, 20],
     [True, False, 20],
     [True, False, 50],
     [True, False, 50],
     [True, True, 10],
     [True, False, 50]]],
   [[False, 0],
    [False, 0],
    [False, 0],
    [False, 10],
    [False, 30],
    [False, 50],
    [True, 100],
    [True, 100],
    [False, 0],
    [False, 50]]],
  ['regression: scenario 4',
   [100,
    [[True, False, 20],
     [True, False, 10],
     [False, False, 20],
     [True, False, 30],
     [False, False, 20],
     [False, False, 30]]],
   [[False, 0], [False, 10], [False, 10], [False, 10], [False, 10], [False, 10]]]],
 [['regression: reset done timer while disabled',
   [50, [[True, False, 30], [True, False, 60], [False, False, 10], [False, True, 10], [False, False, 10]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 0]]],
  ['regression: scenario 3',
   [50,
    [[True, True, 10],
     [True, False, 20],
     [True, False, 10],
     [True, False, 20],
     [True, False, 40],
     [True, False, 50],
     [True, False, 30],
     [False, False, 20],
     [True, False, 40],
     [False, True, 20]]],
   [[False, 0],
    [False, 20],
    [False, 30],
    [True, 50],
    [True, 50],
    [True, 50],
    [True, 50],
    [True, 50],
    [True, 50],
    [False, 0]]],
  ['regression: interrupted timing retained',
   [100,
    [[True, False, 30],
     [True, False, 40],
     [False, False, 40],
     [True, False, 40],
     [True, False, 40],
     [True, False, 40]]],
   [[False, 0], [False, 40], [False, 40], [False, 40], [False, 80], [True, 100]]],
  ['control: reset while enabled',
   [100, [[True, False, 30], [True, False, 60], [True, True, 30], [True, False, 30], [True, False, 30]]],
   [[False, 0], [False, 60], [False, 0], [False, 30], [False, 60]]],
  ['control: reset done timer while enabled',
   [50,
    [[True, False, 30],
     [True, False, 60],
     [True, False, 10],
     [True, True, 10],
     [True, False, 25],
     [True, False, 25]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 25], [True, 50]]],
  ['regression: scenario 1',
   [80,
    [[False, False, 10],
     [True, False, 30],
     [True, False, 10],
     [True, True, 40],
     [True, False, 50],
     [False, False, 40],
     [False, False, 50],
     [False, False, 40]]],
   [[False, 0], [False, 0], [False, 10], [False, 0], [False, 50], [False, 50], [False, 50], [False, 50]]],
  ['regression: scenario 2',
   [0,
    [[True, False, 10],
     [False, False, 30],
     [True, False, 20],
     [True, False, 30],
     [True, False, 50],
     [True, False, 50],
     [True, True, 20],
     [True, False, 20],
     [False, False, 40]]],
   [[True, 0], [True, 0], [True, 0], [True, 0], [True, 0], [True, 0], [False, 0], [True, 0], [True, 0]]],
  ['control: scenario 4',
   [80,
    [[False, False, 20],
     [False, False, 40],
     [True, False, 50],
     [True, False, 40],
     [True, True, 40],
     [False, False, 10],
     [True, False, 10],
     [True, False, 30],
     [True, False, 50],
     [True, False, 40],
     [False, True, 30]]],
   [[False, 0],
    [False, 0],
    [False, 0],
    [False, 40],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 30],
    [True, 80],
    [True, 80],
    [False, 0]]]],
 [['regression: scenario 1',
   [0,
    [[False, False, 40],
     [False, True, 30],
     [True, False, 10],
     [True, False, 30],
     [True, False, 20],
     [False, True, 30],
     [True, False, 40],
     [True, False, 30],
     [True, False, 30],
     [False, False, 20],
     [False, False, 10],
     [True, False, 30],
     [True, False, 50],
     [False, False, 10]]],
   [[False, 0],
    [False, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [False, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0]]],
  ['regression: scenario 5',
   [100,
    [[True, False, 10],
     [True, False, 40],
     [True, False, 20],
     [True, False, 10],
     [True, False, 30],
     [True, False, 50],
     [False, False, 50],
     [True, False, 30],
     [True, False, 40],
     [False, False, 30]]],
   [[False, 0],
    [False, 40],
    [False, 60],
    [False, 70],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100]]],
  ['regression: interrupted timing retained',
   [100,
    [[True, False, 30],
     [True, False, 40],
     [False, False, 40],
     [True, False, 40],
     [True, False, 40],
     [True, False, 40]]],
   [[False, 0], [False, 40], [False, 40], [False, 40], [False, 80], [True, 100]]],
  ['control: reset while enabled',
   [100, [[True, False, 30], [True, False, 60], [True, True, 30], [True, False, 30], [True, False, 30]]],
   [[False, 0], [False, 60], [False, 0], [False, 30], [False, 60]]],
  ['control: reset done timer while enabled',
   [50,
    [[True, False, 30],
     [True, False, 60],
     [True, False, 10],
     [True, True, 10],
     [True, False, 25],
     [True, False, 25]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 25], [True, 50]]],
  ['regression: reset done timer while disabled',
   [50, [[True, False, 30], [True, False, 60], [False, False, 10], [False, True, 10], [False, False, 10]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 0]]],
  ['regression: scenario 2',
   [50,
    [[True, False, 10],
     [True, False, 20],
     [True, False, 50],
     [True, False, 20],
     [True, False, 20],
     [False, False, 50],
     [False, False, 40],
     [False, True, 10],
     [False, False, 10]]],
   [[False, 0],
    [False, 20],
    [True, 50],
    [True, 50],
    [True, 50],
    [True, 50],
    [True, 50],
    [False, 0],
    [False, 0]]],
  ['regression: scenario 3',
   [150,
    [[True, False, 50],
     [True, False, 30],
     [False, False, 50],
     [False, False, 40],
     [False, False, 50],
     [False, False, 20]]],
   [[False, 0], [False, 30], [False, 30], [False, 30], [False, 30], [False, 30]]]],
 [['regression: scenario 2',
   [100,
    [[True, False, 20],
     [True, False, 30],
     [True, False, 10],
     [True, True, 10],
     [True, False, 10],
     [True, False, 20],
     [False, False, 50],
     [False, True, 40],
     [False, False, 30],
     [False, False, 40],
     [True, False, 10],
     [True, False, 50]]],
   [[False, 0],
    [False, 30],
    [False, 40],
    [False, 0],
    [False, 10],
    [False, 30],
    [False, 30],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 50]]],
  ['regression: scenario 11',
   [100,
    [[True, False, 20],
     [True, True, 30],
     [True, True, 20],
     [True, False, 50],
     [True, False, 50],
     [True, False, 30],
     [False, False, 40],
     [True, False, 50],
     [False, False, 40]]],
   [[False, 0],
    [False, 0],
    [False, 0],
    [False, 50],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100]]],
  ['regression: interrupted timing retained',
   [100,
    [[True, False, 30],
     [True, False, 40],
     [False, False, 40],
     [True, False, 40],
     [True, False, 40],
     [True, False, 40]]],
   [[False, 0], [False, 40], [False, 40], [False, 40], [False, 80], [True, 100]]],
  ['control: reset while enabled',
   [100, [[True, False, 30], [True, False, 60], [True, True, 30], [True, False, 30], [True, False, 30]]],
   [[False, 0], [False, 60], [False, 0], [False, 30], [False, 60]]],
  ['control: reset done timer while enabled',
   [50,
    [[True, False, 30],
     [True, False, 60],
     [True, False, 10],
     [True, True, 10],
     [True, False, 25],
     [True, False, 25]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 25], [True, 50]]],
  ['regression: reset done timer while disabled',
   [50, [[True, False, 30], [True, False, 60], [False, False, 10], [False, True, 10], [False, False, 10]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 0]]],
  ['regression: scenario 1',
   [0,
    [[False, False, 50],
     [False, False, 20],
     [False, False, 30],
     [True, True, 40],
     [False, True, 10],
     [True, False, 10],
     [False, False, 30]]],
   [[False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [True, 0], [True, 0]]],
  ['control: scenario 3',
   [100,
    [[False, False, 10],
     [True, False, 20],
     [True, False, 10],
     [True, True, 50],
     [True, False, 40],
     [True, False, 50],
     [False, True, 50],
     [False, False, 10],
     [True, False, 30]]],
   [[False, 0],
    [False, 0],
    [False, 10],
    [False, 0],
    [False, 40],
    [False, 90],
    [False, 0],
    [False, 0],
    [False, 0]]]],
 [['regression: scenario 5',
   [150,
    [[True, False, 50],
     [True, False, 30],
     [False, False, 40],
     [True, False, 50],
     [True, False, 40],
     [False, False, 50],
     [False, False, 20],
     [False, False, 50],
     [True, False, 40],
     [False, False, 40],
     [True, True, 10]]],
   [[False, 0],
    [False, 30],
    [False, 30],
    [False, 30],
    [False, 70],
    [False, 70],
    [False, 70],
    [False, 70],
    [False, 70],
    [False, 70],
    [False, 0]]],
  ['regression: scenario 13',
   [0,
    [[True, False, 10],
     [True, False, 50],
     [True, False, 50],
     [False, False, 30],
     [False, False, 20],
     [True, False, 10],
     [True, False, 50],
     [True, True, 50],
     [False, False, 10],
     [True, True, 30],
     [True, False, 40],
     [False, False, 20]]],
   [[True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [True, 0],
    [True, 0]]],
  ['regression: interrupted timing retained',
   [100,
    [[True, False, 30],
     [True, False, 40],
     [False, False, 40],
     [True, False, 40],
     [True, False, 40],
     [True, False, 40]]],
   [[False, 0], [False, 40], [False, 40], [False, 40], [False, 80], [True, 100]]],
  ['control: reset while enabled',
   [100, [[True, False, 30], [True, False, 60], [True, True, 30], [True, False, 30], [True, False, 30]]],
   [[False, 0], [False, 60], [False, 0], [False, 30], [False, 60]]],
  ['control: reset done timer while enabled',
   [50,
    [[True, False, 30],
     [True, False, 60],
     [True, False, 10],
     [True, True, 10],
     [True, False, 25],
     [True, False, 25]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 25], [True, 50]]],
  ['regression: reset done timer while disabled',
   [50, [[True, False, 30], [True, False, 60], [False, False, 10], [False, True, 10], [False, False, 10]]],
   [[False, 0], [True, 50], [True, 50], [False, 0], [False, 0]]],
  ['regression: scenario 1',
   [0,
    [[True, False, 30],
     [True, False, 10],
     [True, False, 10],
     [True, False, 40],
     [False, False, 30],
     [False, False, 50],
     [False, True, 40],
     [True, False, 10],
     [True, False, 30],
     [True, False, 50],
     [False, False, 20],
     [False, False, 30],
     [False, False, 40],
     [False, False, 50]]],
   [[True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [False, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0],
    [True, 0]]],
  ['control: scenario 2',
   [50,
    [[True, True, 50],
     [False, False, 10],
     [True, False, 50],
     [False, True, 50],
     [False, False, 20],
     [True, False, 20]]],
   [[False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0]]]]]
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: interrupted timing retained[[False, 0], [False, 40], [False, 40], [False, 40], [False, 80], [True, 100]][[False, 0], [False, 40], [False, 40], [False, 40], [False, 80], [True, 100]]Passed
regression: reset done timer while disabled[[False, 0], [True, 50], [True, 50], [False, 0], [False, 0]][[False, 0], [True, 50], [True, 50], [False, 0], [False, 0]]Passed
control: reset while enabled[[False, 0], [False, 60], [False, 0], [False, 30], [False, 60]][[False, 0], [False, 60], [False, 0], [False, 30], [False, 60]]Passed
control: reset done timer while enabled[[False, 0], [True, 50], [True, 50], [False, 0], [False, 25], [True, 50]][[False, 0], [True, 50], [True, 50], [False, 0], [False, 25], [True, 50]]Passed
regression: scenario 1[[False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 20], [False, 20]][[False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 20], [False, 20]]Passed
control: scenario 2[[False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 40]][[False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 0], [False, 40]]Passed
control: scenario 3[[False, 0], [False, 0], [False, 0], [False, 10], [False, 30], [False, 50], [True, 100], [True, 100], [False, 0], [False, 50]][[False, 0], [False, 0], [False, 0], [False, 10], [False, 30], [False, 50], [True, 100], [True, 100], [False, 0], [False, 50]]Passed
regression: scenario 4[[False, 0], [False, 10], [False, 10], [False, 10], [False, 10], [False, 10]][[False, 0], [False, 10], [False, 10], [False, 10], [False, 10], [False, 10]]Passed

SHA-256 / e0bb0bf5bfc42f6b0a90bfd61e909ad1520a22653ab94ed8909572e247049917

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 2026-09-29T14:51:40.436435+00:00.

Case digest / 6491917241d469d3097a25c39587af5e2d239b2a991f2896e32655a8ea50d37c