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FA-64546 / Clinical triage scoring / Open access

Waiting room queue ordering with overdue escalation: overdue target level · case 01

A downgraded patient is flagged overdue against the old, shorter target.

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

ROOT CAUSE

The waiting target is looked up with the original level instead of the effective level.

VERIFIED REPAIR

Compare the wait with the target for the effective level.

Unsuccessful approach: Using the more urgent of the two levels still applies the old target after a downgrade.

Case contract

Input {now, patients [{id, level, arrival, retriage (or null)}]}. Effective level = retriage when present (up or down), else level. Target waits: 1:0, 2:10, 3:30, 4:60, 5:120 minutes. A patient whose wait strictly exceeds the target of the effective level is overdue and moves up one priority (never above 1). Order by (priority, arrival, id). Return {order, overdue (sorted ids)}.

Why this case matters

Queue ordering with re-triage and time escalation mixes several keys; the chosen level, comparison and tie-break are separate faults.

1 / The failure

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

N = 1
observations = []
def solve(x):
    target = {1: 0, 2: 10, 3: 30, 4: 60, 5: 120}
    rows, overdue = [], []
    for p in x['patients']:
        lvl = p['retriage'] if p['retriage'] is not None else p['level']
        wait = x['now'] - p['arrival']
        pr = lvl
        if wait > target[p['level']]:
            overdue.append(p['id'])
            pr = max(1, lvl - 1)
        rows.append((pr, p['arrival'], p['id']))
    rows.sort()
    return {'order': [r[2] for r in rows], 'overdue': sorted(overdue)}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('downgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 95, 'retriage': 4},
                 {'id': 'b', 'level': 3, 'arrival': 91, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('upgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 4, 'arrival': 90, 'retriage': 2},
                 {'id': 'b', 'level': 3, 'arrival': 81, 'retriage': None}]},
   {'order': ['a', 'b'], 'overdue': []}),
  ('downgraded patient overdue by new target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 79, 'retriage': 3},
                 {'id': 'b', 'level': 2, 'arrival': 95, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('wait exactly at target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 3, 'arrival': 70, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 93, 'retriage': None},
                 {'id': 'c', 'level': 1, 'arrival': 100, 'retriage': None}]},
   {'order': ['c', 'b', 'a'], 'overdue': []}),
  ('level one waiting',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 98, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 50, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated level two ties with level one',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 91, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 80, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated three ties with native two',
   {'now': 200,
    'patients': [{'id': 'x', 'level': 2, 'arrival': 194, 'retriage': None},
                 {'id': 'y', 'level': 3, 'arrival': 150, 'retriage': None}]},
   {'order': ['y', 'x'], 'overdue': ['y']}),
  ('same arrival id tie-break',
   {'now': 60,
    'patients': [{'id': 'b1', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'a1', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'c', 'level': 4, 'arrival': 11, 'retriage': None}]},
   {'order': ['c', 'a1', 'b1'], 'overdue': []})],
 [('downgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 95, 'retriage': 4},
                 {'id': 'b', 'level': 3, 'arrival': 92, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('upgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 4, 'arrival': 90, 'retriage': 2},
                 {'id': 'b', 'level': 3, 'arrival': 82, 'retriage': None}]},
   {'order': ['a', 'b'], 'overdue': []}),
  ('downgraded patient overdue by new target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 78, 'retriage': 3},
                 {'id': 'b', 'level': 2, 'arrival': 95, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('wait exactly at target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 3, 'arrival': 70, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 94, 'retriage': None},
                 {'id': 'c', 'level': 1, 'arrival': 100, 'retriage': None}]},
   {'order': ['c', 'b', 'a'], 'overdue': []}),
  ('level one waiting',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 97, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 50, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated level two ties with level one',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 92, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 80, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated three ties with native two',
   {'now': 200,
    'patients': [{'id': 'x', 'level': 2, 'arrival': 193, 'retriage': None},
                 {'id': 'y', 'level': 3, 'arrival': 150, 'retriage': None}]},
   {'order': ['y', 'x'], 'overdue': ['y']}),
  ('same arrival id tie-break',
   {'now': 60,
    'patients': [{'id': 'b2', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'a2', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'c', 'level': 4, 'arrival': 12, 'retriage': None}]},
   {'order': ['c', 'a2', 'b2'], 'overdue': []})],
 [('downgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 95, 'retriage': 4},
                 {'id': 'b', 'level': 3, 'arrival': 93, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('upgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 4, 'arrival': 90, 'retriage': 2},
                 {'id': 'b', 'level': 3, 'arrival': 83, 'retriage': None}]},
   {'order': ['a', 'b'], 'overdue': []}),
  ('downgraded patient overdue by new target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 77, 'retriage': 3},
                 {'id': 'b', 'level': 2, 'arrival': 95, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('wait exactly at target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 3, 'arrival': 70, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 95, 'retriage': None},
                 {'id': 'c', 'level': 1, 'arrival': 100, 'retriage': None}]},
   {'order': ['c', 'b', 'a'], 'overdue': []}),
  ('level one waiting',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 96, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 50, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated level two ties with level one',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 93, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 80, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated three ties with native two',
   {'now': 200,
    'patients': [{'id': 'x', 'level': 2, 'arrival': 192, 'retriage': None},
                 {'id': 'y', 'level': 3, 'arrival': 150, 'retriage': None}]},
   {'order': ['y', 'x'], 'overdue': ['y']}),
  ('same arrival id tie-break',
   {'now': 60,
    'patients': [{'id': 'b3', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'a3', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'c', 'level': 4, 'arrival': 13, 'retriage': None}]},
   {'order': ['c', 'a3', 'b3'], 'overdue': []})],
 [('downgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 95, 'retriage': 4},
                 {'id': 'b', 'level': 3, 'arrival': 94, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('upgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 4, 'arrival': 90, 'retriage': 2},
                 {'id': 'b', 'level': 3, 'arrival': 84, 'retriage': None}]},
   {'order': ['a', 'b'], 'overdue': []}),
  ('downgraded patient overdue by new target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 76, 'retriage': 3},
                 {'id': 'b', 'level': 2, 'arrival': 95, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('wait exactly at target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 3, 'arrival': 70, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 96, 'retriage': None},
                 {'id': 'c', 'level': 1, 'arrival': 100, 'retriage': None}]},
   {'order': ['c', 'b', 'a'], 'overdue': []}),
  ('level one waiting',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 95, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 50, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated level two ties with level one',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 94, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 80, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated three ties with native two',
   {'now': 200,
    'patients': [{'id': 'x', 'level': 2, 'arrival': 191, 'retriage': None},
                 {'id': 'y', 'level': 3, 'arrival': 150, 'retriage': None}]},
   {'order': ['y', 'x'], 'overdue': ['y']}),
  ('same arrival id tie-break',
   {'now': 60,
    'patients': [{'id': 'b4', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'a4', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'c', 'level': 4, 'arrival': 14, 'retriage': None}]},
   {'order': ['c', 'a4', 'b4'], 'overdue': []})],
 [('downgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 95, 'retriage': 4},
                 {'id': 'b', 'level': 3, 'arrival': 95, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('upgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 4, 'arrival': 90, 'retriage': 2},
                 {'id': 'b', 'level': 3, 'arrival': 85, 'retriage': None}]},
   {'order': ['a', 'b'], 'overdue': []}),
  ('downgraded patient overdue by new target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 75, 'retriage': 3},
                 {'id': 'b', 'level': 2, 'arrival': 95, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('wait exactly at target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 3, 'arrival': 70, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 97, 'retriage': None},
                 {'id': 'c', 'level': 1, 'arrival': 100, 'retriage': None}]},
   {'order': ['c', 'b', 'a'], 'overdue': []}),
  ('level one waiting',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 94, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 50, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated level two ties with level one',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 95, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 80, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated three ties with native two',
   {'now': 200,
    'patients': [{'id': 'x', 'level': 2, 'arrival': 190, 'retriage': None},
                 {'id': 'y', 'level': 3, 'arrival': 150, 'retriage': None}]},
   {'order': ['y', 'x'], 'overdue': ['y']}),
  ('same arrival id tie-break',
   {'now': 60,
    'patients': [{'id': 'b5', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'a5', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'c', 'level': 4, 'arrival': 15, 'retriage': None}]},
   {'order': ['c', 'a5', 'b5'], 'overdue': []})]]
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
downgraded on re-triage{'order': ['b', 'a'], 'overdue': []}{'order': ['b', 'a'], 'overdue': []}Passed
upgraded on re-triage{'order': ['a', 'b'], 'overdue': []}{'order': ['a', 'b'], 'overdue': []}Passed
downgraded patient overdue by new target{'order': ['a', 'b'], 'overdue': ['a']}{'order': ['b', 'a'], 'overdue': []}Failed
wait exactly at target{'order': ['c', 'b', 'a'], 'overdue': []}{'order': ['c', 'b', 'a'], 'overdue': []}Passed
level one waiting{'order': ['b', 'a'], 'overdue': ['a', 'b']}{'order': ['b', 'a'], 'overdue': ['a', 'b']}Passed
escalated level two ties with level one{'order': ['b', 'a'], 'overdue': ['a', 'b']}{'order': ['b', 'a'], 'overdue': ['a', 'b']}Passed
escalated three ties with native two{'order': ['y', 'x'], 'overdue': ['y']}{'order': ['y', 'x'], 'overdue': ['y']}Passed
same arrival id tie-break{'order': ['c', 'a1', 'b1'], 'overdue': []}{'order': ['c', 'a1', 'b1'], 'overdue': []}Passed

SHA-256 / c892a8b2f4aa8c1d86bf91c4ca63e335ecdffe697111ac870b50ae4bcc028283

2 / The unsuccessful fix

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

N = 1
observations = []
def solve(x):
    target = {1: 0, 2: 10, 3: 30, 4: 60, 5: 120}
    rows, overdue = [], []
    for p in x['patients']:
        lvl = p['retriage'] if p['retriage'] is not None else p['level']
        wait = x['now'] - p['arrival']
        pr = lvl
        if wait > target[min(lvl, p['level'])]:
            overdue.append(p['id'])
            pr = max(1, lvl - 1)
        rows.append((pr, p['arrival'], p['id']))
    rows.sort()
    return {'order': [r[2] for r in rows], 'overdue': sorted(overdue)}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('downgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 95, 'retriage': 4},
                 {'id': 'b', 'level': 3, 'arrival': 91, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('upgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 4, 'arrival': 90, 'retriage': 2},
                 {'id': 'b', 'level': 3, 'arrival': 81, 'retriage': None}]},
   {'order': ['a', 'b'], 'overdue': []}),
  ('downgraded patient overdue by new target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 79, 'retriage': 3},
                 {'id': 'b', 'level': 2, 'arrival': 95, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('wait exactly at target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 3, 'arrival': 70, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 93, 'retriage': None},
                 {'id': 'c', 'level': 1, 'arrival': 100, 'retriage': None}]},
   {'order': ['c', 'b', 'a'], 'overdue': []}),
  ('level one waiting',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 98, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 50, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated level two ties with level one',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 91, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 80, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated three ties with native two',
   {'now': 200,
    'patients': [{'id': 'x', 'level': 2, 'arrival': 194, 'retriage': None},
                 {'id': 'y', 'level': 3, 'arrival': 150, 'retriage': None}]},
   {'order': ['y', 'x'], 'overdue': ['y']}),
  ('same arrival id tie-break',
   {'now': 60,
    'patients': [{'id': 'b1', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'a1', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'c', 'level': 4, 'arrival': 11, 'retriage': None}]},
   {'order': ['c', 'a1', 'b1'], 'overdue': []})],
 [('downgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 95, 'retriage': 4},
                 {'id': 'b', 'level': 3, 'arrival': 92, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('upgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 4, 'arrival': 90, 'retriage': 2},
                 {'id': 'b', 'level': 3, 'arrival': 82, 'retriage': None}]},
   {'order': ['a', 'b'], 'overdue': []}),
  ('downgraded patient overdue by new target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 78, 'retriage': 3},
                 {'id': 'b', 'level': 2, 'arrival': 95, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('wait exactly at target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 3, 'arrival': 70, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 94, 'retriage': None},
                 {'id': 'c', 'level': 1, 'arrival': 100, 'retriage': None}]},
   {'order': ['c', 'b', 'a'], 'overdue': []}),
  ('level one waiting',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 97, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 50, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated level two ties with level one',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 92, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 80, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated three ties with native two',
   {'now': 200,
    'patients': [{'id': 'x', 'level': 2, 'arrival': 193, 'retriage': None},
                 {'id': 'y', 'level': 3, 'arrival': 150, 'retriage': None}]},
   {'order': ['y', 'x'], 'overdue': ['y']}),
  ('same arrival id tie-break',
   {'now': 60,
    'patients': [{'id': 'b2', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'a2', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'c', 'level': 4, 'arrival': 12, 'retriage': None}]},
   {'order': ['c', 'a2', 'b2'], 'overdue': []})],
 [('downgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 95, 'retriage': 4},
                 {'id': 'b', 'level': 3, 'arrival': 93, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('upgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 4, 'arrival': 90, 'retriage': 2},
                 {'id': 'b', 'level': 3, 'arrival': 83, 'retriage': None}]},
   {'order': ['a', 'b'], 'overdue': []}),
  ('downgraded patient overdue by new target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 77, 'retriage': 3},
                 {'id': 'b', 'level': 2, 'arrival': 95, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('wait exactly at target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 3, 'arrival': 70, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 95, 'retriage': None},
                 {'id': 'c', 'level': 1, 'arrival': 100, 'retriage': None}]},
   {'order': ['c', 'b', 'a'], 'overdue': []}),
  ('level one waiting',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 96, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 50, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated level two ties with level one',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 93, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 80, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated three ties with native two',
   {'now': 200,
    'patients': [{'id': 'x', 'level': 2, 'arrival': 192, 'retriage': None},
                 {'id': 'y', 'level': 3, 'arrival': 150, 'retriage': None}]},
   {'order': ['y', 'x'], 'overdue': ['y']}),
  ('same arrival id tie-break',
   {'now': 60,
    'patients': [{'id': 'b3', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'a3', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'c', 'level': 4, 'arrival': 13, 'retriage': None}]},
   {'order': ['c', 'a3', 'b3'], 'overdue': []})],
 [('downgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 95, 'retriage': 4},
                 {'id': 'b', 'level': 3, 'arrival': 94, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('upgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 4, 'arrival': 90, 'retriage': 2},
                 {'id': 'b', 'level': 3, 'arrival': 84, 'retriage': None}]},
   {'order': ['a', 'b'], 'overdue': []}),
  ('downgraded patient overdue by new target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 76, 'retriage': 3},
                 {'id': 'b', 'level': 2, 'arrival': 95, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('wait exactly at target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 3, 'arrival': 70, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 96, 'retriage': None},
                 {'id': 'c', 'level': 1, 'arrival': 100, 'retriage': None}]},
   {'order': ['c', 'b', 'a'], 'overdue': []}),
  ('level one waiting',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 95, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 50, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated level two ties with level one',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 94, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 80, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated three ties with native two',
   {'now': 200,
    'patients': [{'id': 'x', 'level': 2, 'arrival': 191, 'retriage': None},
                 {'id': 'y', 'level': 3, 'arrival': 150, 'retriage': None}]},
   {'order': ['y', 'x'], 'overdue': ['y']}),
  ('same arrival id tie-break',
   {'now': 60,
    'patients': [{'id': 'b4', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'a4', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'c', 'level': 4, 'arrival': 14, 'retriage': None}]},
   {'order': ['c', 'a4', 'b4'], 'overdue': []})],
 [('downgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 95, 'retriage': 4},
                 {'id': 'b', 'level': 3, 'arrival': 95, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('upgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 4, 'arrival': 90, 'retriage': 2},
                 {'id': 'b', 'level': 3, 'arrival': 85, 'retriage': None}]},
   {'order': ['a', 'b'], 'overdue': []}),
  ('downgraded patient overdue by new target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 75, 'retriage': 3},
                 {'id': 'b', 'level': 2, 'arrival': 95, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('wait exactly at target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 3, 'arrival': 70, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 97, 'retriage': None},
                 {'id': 'c', 'level': 1, 'arrival': 100, 'retriage': None}]},
   {'order': ['c', 'b', 'a'], 'overdue': []}),
  ('level one waiting',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 94, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 50, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated level two ties with level one',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 95, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 80, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated three ties with native two',
   {'now': 200,
    'patients': [{'id': 'x', 'level': 2, 'arrival': 190, 'retriage': None},
                 {'id': 'y', 'level': 3, 'arrival': 150, 'retriage': None}]},
   {'order': ['y', 'x'], 'overdue': ['y']}),
  ('same arrival id tie-break',
   {'now': 60,
    'patients': [{'id': 'b5', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'a5', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'c', 'level': 4, 'arrival': 15, 'retriage': None}]},
   {'order': ['c', 'a5', 'b5'], 'overdue': []})]]
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
downgraded on re-triage{'order': ['b', 'a'], 'overdue': []}{'order': ['b', 'a'], 'overdue': []}Passed
upgraded on re-triage{'order': ['a', 'b'], 'overdue': []}{'order': ['a', 'b'], 'overdue': []}Passed
downgraded patient overdue by new target{'order': ['a', 'b'], 'overdue': ['a']}{'order': ['b', 'a'], 'overdue': []}Failed
wait exactly at target{'order': ['c', 'b', 'a'], 'overdue': []}{'order': ['c', 'b', 'a'], 'overdue': []}Passed
level one waiting{'order': ['b', 'a'], 'overdue': ['a', 'b']}{'order': ['b', 'a'], 'overdue': ['a', 'b']}Passed
escalated level two ties with level one{'order': ['b', 'a'], 'overdue': ['a', 'b']}{'order': ['b', 'a'], 'overdue': ['a', 'b']}Passed
escalated three ties with native two{'order': ['y', 'x'], 'overdue': ['y']}{'order': ['y', 'x'], 'overdue': ['y']}Passed
same arrival id tie-break{'order': ['c', 'a1', 'b1'], 'overdue': []}{'order': ['c', 'a1', 'b1'], 'overdue': []}Passed

SHA-256 / fe56b736afafa1dcf8320cdceb0e075377ca6ae104cbce0c31a26a3e5a43a9aa

3 / The verified repair

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

N = 1
observations = []
def solve(x):
    target = {1: 0, 2: 10, 3: 30, 4: 60, 5: 120}
    rows, overdue = [], []
    for p in x['patients']:
        lvl = p['retriage'] if p['retriage'] is not None else p['level']
        wait = x['now'] - p['arrival']
        pr = lvl
        if wait > target[lvl]:
            overdue.append(p['id'])
            pr = max(1, lvl - 1)
        rows.append((pr, p['arrival'], p['id']))
    rows.sort()
    return {'order': [r[2] for r in rows], 'overdue': sorted(overdue)}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[('downgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 95, 'retriage': 4},
                 {'id': 'b', 'level': 3, 'arrival': 91, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('upgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 4, 'arrival': 90, 'retriage': 2},
                 {'id': 'b', 'level': 3, 'arrival': 81, 'retriage': None}]},
   {'order': ['a', 'b'], 'overdue': []}),
  ('downgraded patient overdue by new target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 79, 'retriage': 3},
                 {'id': 'b', 'level': 2, 'arrival': 95, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('wait exactly at target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 3, 'arrival': 70, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 93, 'retriage': None},
                 {'id': 'c', 'level': 1, 'arrival': 100, 'retriage': None}]},
   {'order': ['c', 'b', 'a'], 'overdue': []}),
  ('level one waiting',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 98, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 50, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated level two ties with level one',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 91, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 80, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated three ties with native two',
   {'now': 200,
    'patients': [{'id': 'x', 'level': 2, 'arrival': 194, 'retriage': None},
                 {'id': 'y', 'level': 3, 'arrival': 150, 'retriage': None}]},
   {'order': ['y', 'x'], 'overdue': ['y']}),
  ('same arrival id tie-break',
   {'now': 60,
    'patients': [{'id': 'b1', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'a1', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'c', 'level': 4, 'arrival': 11, 'retriage': None}]},
   {'order': ['c', 'a1', 'b1'], 'overdue': []})],
 [('downgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 95, 'retriage': 4},
                 {'id': 'b', 'level': 3, 'arrival': 92, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('upgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 4, 'arrival': 90, 'retriage': 2},
                 {'id': 'b', 'level': 3, 'arrival': 82, 'retriage': None}]},
   {'order': ['a', 'b'], 'overdue': []}),
  ('downgraded patient overdue by new target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 78, 'retriage': 3},
                 {'id': 'b', 'level': 2, 'arrival': 95, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('wait exactly at target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 3, 'arrival': 70, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 94, 'retriage': None},
                 {'id': 'c', 'level': 1, 'arrival': 100, 'retriage': None}]},
   {'order': ['c', 'b', 'a'], 'overdue': []}),
  ('level one waiting',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 97, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 50, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated level two ties with level one',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 92, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 80, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated three ties with native two',
   {'now': 200,
    'patients': [{'id': 'x', 'level': 2, 'arrival': 193, 'retriage': None},
                 {'id': 'y', 'level': 3, 'arrival': 150, 'retriage': None}]},
   {'order': ['y', 'x'], 'overdue': ['y']}),
  ('same arrival id tie-break',
   {'now': 60,
    'patients': [{'id': 'b2', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'a2', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'c', 'level': 4, 'arrival': 12, 'retriage': None}]},
   {'order': ['c', 'a2', 'b2'], 'overdue': []})],
 [('downgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 95, 'retriage': 4},
                 {'id': 'b', 'level': 3, 'arrival': 93, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('upgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 4, 'arrival': 90, 'retriage': 2},
                 {'id': 'b', 'level': 3, 'arrival': 83, 'retriage': None}]},
   {'order': ['a', 'b'], 'overdue': []}),
  ('downgraded patient overdue by new target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 77, 'retriage': 3},
                 {'id': 'b', 'level': 2, 'arrival': 95, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('wait exactly at target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 3, 'arrival': 70, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 95, 'retriage': None},
                 {'id': 'c', 'level': 1, 'arrival': 100, 'retriage': None}]},
   {'order': ['c', 'b', 'a'], 'overdue': []}),
  ('level one waiting',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 96, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 50, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated level two ties with level one',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 93, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 80, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated three ties with native two',
   {'now': 200,
    'patients': [{'id': 'x', 'level': 2, 'arrival': 192, 'retriage': None},
                 {'id': 'y', 'level': 3, 'arrival': 150, 'retriage': None}]},
   {'order': ['y', 'x'], 'overdue': ['y']}),
  ('same arrival id tie-break',
   {'now': 60,
    'patients': [{'id': 'b3', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'a3', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'c', 'level': 4, 'arrival': 13, 'retriage': None}]},
   {'order': ['c', 'a3', 'b3'], 'overdue': []})],
 [('downgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 95, 'retriage': 4},
                 {'id': 'b', 'level': 3, 'arrival': 94, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('upgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 4, 'arrival': 90, 'retriage': 2},
                 {'id': 'b', 'level': 3, 'arrival': 84, 'retriage': None}]},
   {'order': ['a', 'b'], 'overdue': []}),
  ('downgraded patient overdue by new target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 76, 'retriage': 3},
                 {'id': 'b', 'level': 2, 'arrival': 95, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('wait exactly at target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 3, 'arrival': 70, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 96, 'retriage': None},
                 {'id': 'c', 'level': 1, 'arrival': 100, 'retriage': None}]},
   {'order': ['c', 'b', 'a'], 'overdue': []}),
  ('level one waiting',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 95, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 50, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated level two ties with level one',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 94, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 80, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated three ties with native two',
   {'now': 200,
    'patients': [{'id': 'x', 'level': 2, 'arrival': 191, 'retriage': None},
                 {'id': 'y', 'level': 3, 'arrival': 150, 'retriage': None}]},
   {'order': ['y', 'x'], 'overdue': ['y']}),
  ('same arrival id tie-break',
   {'now': 60,
    'patients': [{'id': 'b4', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'a4', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'c', 'level': 4, 'arrival': 14, 'retriage': None}]},
   {'order': ['c', 'a4', 'b4'], 'overdue': []})],
 [('downgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 95, 'retriage': 4},
                 {'id': 'b', 'level': 3, 'arrival': 95, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('upgraded on re-triage',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 4, 'arrival': 90, 'retriage': 2},
                 {'id': 'b', 'level': 3, 'arrival': 85, 'retriage': None}]},
   {'order': ['a', 'b'], 'overdue': []}),
  ('downgraded patient overdue by new target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 2, 'arrival': 75, 'retriage': 3},
                 {'id': 'b', 'level': 2, 'arrival': 95, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': []}),
  ('wait exactly at target',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 3, 'arrival': 70, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 97, 'retriage': None},
                 {'id': 'c', 'level': 1, 'arrival': 100, 'retriage': None}]},
   {'order': ['c', 'b', 'a'], 'overdue': []}),
  ('level one waiting',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 94, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 50, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated level two ties with level one',
   {'now': 100,
    'patients': [{'id': 'a', 'level': 1, 'arrival': 95, 'retriage': None},
                 {'id': 'b', 'level': 2, 'arrival': 80, 'retriage': None}]},
   {'order': ['b', 'a'], 'overdue': ['a', 'b']}),
  ('escalated three ties with native two',
   {'now': 200,
    'patients': [{'id': 'x', 'level': 2, 'arrival': 190, 'retriage': None},
                 {'id': 'y', 'level': 3, 'arrival': 150, 'retriage': None}]},
   {'order': ['y', 'x'], 'overdue': ['y']}),
  ('same arrival id tie-break',
   {'now': 60,
    'patients': [{'id': 'b5', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'a5', 'level': 4, 'arrival': 30, 'retriage': None},
                 {'id': 'c', 'level': 4, 'arrival': 15, 'retriage': None}]},
   {'order': ['c', 'a5', 'b5'], 'overdue': []})]]
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
downgraded on re-triage{'order': ['b', 'a'], 'overdue': []}{'order': ['b', 'a'], 'overdue': []}Passed
upgraded on re-triage{'order': ['a', 'b'], 'overdue': []}{'order': ['a', 'b'], 'overdue': []}Passed
downgraded patient overdue by new target{'order': ['b', 'a'], 'overdue': []}{'order': ['b', 'a'], 'overdue': []}Passed
wait exactly at target{'order': ['c', 'b', 'a'], 'overdue': []}{'order': ['c', 'b', 'a'], 'overdue': []}Passed
level one waiting{'order': ['b', 'a'], 'overdue': ['a', 'b']}{'order': ['b', 'a'], 'overdue': ['a', 'b']}Passed
escalated level two ties with level one{'order': ['b', 'a'], 'overdue': ['a', 'b']}{'order': ['b', 'a'], 'overdue': ['a', 'b']}Passed
escalated three ties with native two{'order': ['y', 'x'], 'overdue': ['y']}{'order': ['y', 'x'], 'overdue': ['y']}Passed
same arrival id tie-break{'order': ['c', 'a1', 'b1'], 'overdue': []}{'order': ['c', 'a1', 'b1'], 'overdue': []}Passed

SHA-256 / f62adb031c731ac44e60793acd3641e89abd24d8ae3d3d788fcccca1667bee0b

Verification & scope

A deterministic toy software model with explicitly stipulated thresholds and formulas; it is not clinical guidance, not a validated medical calculator, and makes no claim of conformance to any published protocol. Numbered variants vary patient and order inputs. 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 2026-09-29T14:47:25.413347+00:00.

Case digest / 91555e16b8aea8163766f61421ec0ee0a52b4f63741a42f3cc38b98fb32536aa