FA-60386 / Loyalty points ledgers / Open access

Expiring point lots: redemption lot order · case 01

Short-lived promotional points expire unused while long-lived points are spent first.

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

ROOT CAUSE

Redemptions draw lots in earn-day order rather than expiry order.

VERIFIED REPAIR

Draw the soonest-expiring lot first, earn day breaking ties.

Unsuccessful approach: Drawing the smallest lots first clears small balances but ignores expiry.

Case contract

Events ["earn",day,pts,ttl] create a lot expiring at day+ttl (usable through that day); ["redeem",day,pts] draws only unexpired lots, soonest expiry first (ties by earn day), rejecting with "insufficient" when unexpired points are short; ["sweep",day] removes lots whose expiry is before day and reports the points removed. Emptied lots are dropped. Return {results, lots:[[expiry, earn_day, pts]]}.

Why this case matters

Member point balances, statements and the program liability depend on this ledger rule.

1 / The failure

Exit 1

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

N = 1
observations = []
def solve(x):
    lots = []
    out = []
    for ev in x['events']:
        kind, day = ev[0], ev[1]
        if kind == 'earn':
            exp = day + ev[3]
            lots.append([exp, day, ev[2]])
            out.append(exp)
        elif kind == 'sweep':
            gone = sum(l[2] for l in lots if l[0] < day)
            lots = [l for l in lots if l[0] >= day]
            out.append(gone)
        else:
            need = ev[2]
            live = sorted([l for l in lots if l[0] >= day], key=lambda l: (l[1], l[0]))
            if need > sum(l[2] for l in live):
                out.append('insufficient')
                continue
            used = []
            for l in live:
                t = min(need, l[2])
                if t > 0:
                    l[2] -= t
                    need -= t
                    used.append([l[0], t])
            lots = [l for l in lots if l[2] > 0]
            out.append(used)
    return {'results': out, 'lots': lots}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['soonest expiry first', {'events': [['earn', 1, 500, 365], ['earn', 10, 300, 31], ['redeem', 20, 400]]}, {'results': [366, 41, [[41, 300], [366, 100]]], 'lots': [[366, 1, 400]]}], ['use on expiry day', {'events': [['earn', 0, 200, 30], ['redeem', 30, 151]]}, {'results': [30, [[30, 151]]], 'lots': [[30, 0, 49]]}], ['expired unusable', {'events': [['earn', 0, 200, 30], ['earn', 5, 50, 90], ['redeem', 31, 101]]}, {'results': [30, 95, 'insufficient'], 'lots': [[30, 0, 200], [95, 5, 50]]}], ['sweep reports points', {'events': [['earn', 0, 120, 10], ['earn', 0, 81, 10], ['earn', 3, 60, 100], ['sweep', 11]]}, {'results': [10, 10, 103, 201], 'lots': [[103, 3, 60]]}], ['sweep boundary', {'events': [['earn', 0, 70, 11], ['sweep', 11], ['sweep', 12]]}, {'results': [11, 0, 70], 'lots': []}], ['partial lot cleanup', {'events': [['earn', 0, 100, 50], ['earn', 1, 100, 60], ['redeem', 2, 100], ['redeem', 3, 31]]}, {'results': [50, 61, [[50, 100]], [[61, 31]]], 'lots': [[61, 1, 69]]}], ['insufficient', {'events': [['earn', 0, 100, 50], ['redeem', 1, 151], ['redeem', 2, 100]]}, {'results': [50, 'insufficient', [[50, 100]]], 'lots': []}], ['ties by earn day', {'events': [['earn', 5, 40, 20], ['earn', 1, 40, 24], ['redeem', 6, 51]]}, {'results': [25, 25, [[25, 40], [25, 11]]], 'lots': [[25, 5, 29]]}]], [['soonest expiry first', {'events': [['earn', 1, 500, 365], ['earn', 10, 300, 32], ['redeem', 20, 400]]}, {'results': [366, 42, [[42, 300], [366, 100]]], 'lots': [[366, 1, 400]]}], ['use on expiry day', {'events': [['earn', 0, 200, 30], ['redeem', 30, 152]]}, {'results': [30, [[30, 152]]], 'lots': [[30, 0, 48]]}], ['expired unusable', {'events': [['earn', 0, 200, 30], ['earn', 5, 50, 90], ['redeem', 31, 102]]}, {'results': [30, 95, 'insufficient'], 'lots': [[30, 0, 200], [95, 5, 50]]}], ['sweep reports points', {'events': [['earn', 0, 120, 10], ['earn', 0, 82, 10], ['earn', 3, 60, 100], ['sweep', 11]]}, {'results': [10, 10, 103, 202], 'lots': [[103, 3, 60]]}], ['sweep boundary', {'events': [['earn', 0, 70, 12], ['sweep', 12], ['sweep', 13]]}, {'results': [12, 0, 70], 'lots': []}], ['partial lot cleanup', {'events': [['earn', 0, 100, 50], ['earn', 1, 100, 60], ['redeem', 2, 100], ['redeem', 3, 32]]}, {'results': [50, 61, [[50, 100]], [[61, 32]]], 'lots': [[61, 1, 68]]}], ['insufficient', {'events': [['earn', 0, 100, 50], ['redeem', 1, 152], ['redeem', 2, 100]]}, {'results': [50, 'insufficient', [[50, 100]]], 'lots': []}], ['ties by earn day', {'events': [['earn', 5, 40, 20], ['earn', 1, 40, 24], ['redeem', 6, 52]]}, {'results': [25, 25, [[25, 40], [25, 12]]], 'lots': [[25, 5, 28]]}]], [['soonest expiry first', {'events': [['earn', 1, 500, 365], ['earn', 10, 300, 33], ['redeem', 20, 400]]}, {'results': [366, 43, [[43, 300], [366, 100]]], 'lots': [[366, 1, 400]]}], ['use on expiry day', {'events': [['earn', 0, 200, 30], ['redeem', 30, 153]]}, {'results': [30, [[30, 153]]], 'lots': [[30, 0, 47]]}], ['expired unusable', {'events': [['earn', 0, 200, 30], ['earn', 5, 50, 90], ['redeem', 31, 103]]}, {'results': [30, 95, 'insufficient'], 'lots': [[30, 0, 200], [95, 5, 50]]}], ['sweep reports points', {'events': [['earn', 0, 120, 10], ['earn', 0, 83, 10], ['earn', 3, 60, 100], ['sweep', 11]]}, {'results': [10, 10, 103, 203], 'lots': [[103, 3, 60]]}], ['sweep boundary', {'events': [['earn', 0, 70, 13], ['sweep', 13], ['sweep', 14]]}, {'results': [13, 0, 70], 'lots': []}], ['partial lot cleanup', {'events': [['earn', 0, 100, 50], ['earn', 1, 100, 60], ['redeem', 2, 100], ['redeem', 3, 33]]}, {'results': [50, 61, [[50, 100]], [[61, 33]]], 'lots': [[61, 1, 67]]}], ['insufficient', {'events': [['earn', 0, 100, 50], ['redeem', 1, 153], ['redeem', 2, 100]]}, {'results': [50, 'insufficient', [[50, 100]]], 'lots': []}], ['ties by earn day', {'events': [['earn', 5, 40, 20], ['earn', 1, 40, 24], ['redeem', 6, 53]]}, {'results': [25, 25, [[25, 40], [25, 13]]], 'lots': [[25, 5, 27]]}]], [['soonest expiry first', {'events': [['earn', 1, 500, 365], ['earn', 10, 300, 34], ['redeem', 20, 400]]}, {'results': [366, 44, [[44, 300], [366, 100]]], 'lots': [[366, 1, 400]]}], ['use on expiry day', {'events': [['earn', 0, 200, 30], ['redeem', 30, 154]]}, {'results': [30, [[30, 154]]], 'lots': [[30, 0, 46]]}], ['expired unusable', {'events': [['earn', 0, 200, 30], ['earn', 5, 50, 90], ['redeem', 31, 104]]}, {'results': [30, 95, 'insufficient'], 'lots': [[30, 0, 200], [95, 5, 50]]}], ['sweep reports points', {'events': [['earn', 0, 120, 10], ['earn', 0, 84, 10], ['earn', 3, 60, 100], ['sweep', 11]]}, {'results': [10, 10, 103, 204], 'lots': [[103, 3, 60]]}], ['sweep boundary', {'events': [['earn', 0, 70, 14], ['sweep', 14], ['sweep', 15]]}, {'results': [14, 0, 70], 'lots': []}], ['partial lot cleanup', {'events': [['earn', 0, 100, 50], ['earn', 1, 100, 60], ['redeem', 2, 100], ['redeem', 3, 34]]}, {'results': [50, 61, [[50, 100]], [[61, 34]]], 'lots': [[61, 1, 66]]}], ['insufficient', {'events': [['earn', 0, 100, 50], ['redeem', 1, 154], ['redeem', 2, 100]]}, {'results': [50, 'insufficient', [[50, 100]]], 'lots': []}], ['ties by earn day', {'events': [['earn', 5, 40, 20], ['earn', 1, 40, 24], ['redeem', 6, 54]]}, {'results': [25, 25, [[25, 40], [25, 14]]], 'lots': [[25, 5, 26]]}]], [['soonest expiry first', {'events': [['earn', 1, 500, 365], ['earn', 10, 300, 35], ['redeem', 20, 400]]}, {'results': [366, 45, [[45, 300], [366, 100]]], 'lots': [[366, 1, 400]]}], ['use on expiry day', {'events': [['earn', 0, 200, 30], ['redeem', 30, 155]]}, {'results': [30, [[30, 155]]], 'lots': [[30, 0, 45]]}], ['expired unusable', {'events': [['earn', 0, 200, 30], ['earn', 5, 50, 90], ['redeem', 31, 105]]}, {'results': [30, 95, 'insufficient'], 'lots': [[30, 0, 200], [95, 5, 50]]}], ['sweep reports points', {'events': [['earn', 0, 120, 10], ['earn', 0, 85, 10], ['earn', 3, 60, 100], ['sweep', 11]]}, {'results': [10, 10, 103, 205], 'lots': [[103, 3, 60]]}], ['sweep boundary', {'events': [['earn', 0, 70, 15], ['sweep', 15], ['sweep', 16]]}, {'results': [15, 0, 70], 'lots': []}], ['partial lot cleanup', {'events': [['earn', 0, 100, 50], ['earn', 1, 100, 60], ['redeem', 2, 100], ['redeem', 3, 35]]}, {'results': [50, 61, [[50, 100]], [[61, 35]]], 'lots': [[61, 1, 65]]}], ['insufficient', {'events': [['earn', 0, 100, 50], ['redeem', 1, 155], ['redeem', 2, 100]]}, {'results': [50, 'insufficient', [[50, 100]]], 'lots': []}], ['ties by earn day', {'events': [['earn', 5, 40, 20], ['earn', 1, 40, 24], ['redeem', 6, 55]]}, {'results': [25, 25, [[25, 40], [25, 15]]], 'lots': [[25, 5, 25]]}]]]
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 fixture	Actual	Expected	Outcome
soonest expiry first	`{'lots': [[366, 1, 100], [41, 10, 300]], 'results': [366, 41, [[366, 400]]]}`	`{'lots': [[366, 1, 400]], 'results': [366, 41, [[41, 300], [366, 100]]]}`	Failed
use on expiry day	`{'lots': [[30, 0, 49]], 'results': [30, [[30, 151]]]}`	`{'lots': [[30, 0, 49]], 'results': [30, [[30, 151]]]}`	Passed
expired unusable	`{'lots': [[30, 0, 200], [95, 5, 50]], 'results': [30, 95, 'insufficient']}`	`{'lots': [[30, 0, 200], [95, 5, 50]], 'results': [30, 95, 'insufficient']}`	Passed
sweep reports points	`{'lots': [[103, 3, 60]], 'results': [10, 10, 103, 201]}`	`{'lots': [[103, 3, 60]], 'results': [10, 10, 103, 201]}`	Passed
sweep boundary	`{'lots': [], 'results': [11, 0, 70]}`	`{'lots': [], 'results': [11, 0, 70]}`	Passed
partial lot cleanup	`{'lots': [[61, 1, 69]], 'results': [50, 61, [[50, 100]], [[61, 31]]]}`	`{'lots': [[61, 1, 69]], 'results': [50, 61, [[50, 100]], [[61, 31]]]}`	Passed
insufficient	`{'lots': [], 'results': [50, 'insufficient', [[50, 100]]]}`	`{'lots': [], 'results': [50, 'insufficient', [[50, 100]]]}`	Passed
ties by earn day	`{'lots': [[25, 5, 29]], 'results': [25, 25, [[25, 40], [25, 11]]]}`	`{'lots': [[25, 5, 29]], 'results': [25, 25, [[25, 40], [25, 11]]]}`	Passed

SHA-256 / 13dc5c423f829113eb5ff8f2ee8ba4d30447bf66eaa8ff4fc44923bd57db17cc

2 / The unsuccessful fix

Exit 1

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

N = 1
observations = []
def solve(x):
    lots = []
    out = []
    for ev in x['events']:
        kind, day = ev[0], ev[1]
        if kind == 'earn':
            exp = day + ev[3]
            lots.append([exp, day, ev[2]])
            out.append(exp)
        elif kind == 'sweep':
            gone = sum(l[2] for l in lots if l[0] < day)
            lots = [l for l in lots if l[0] >= day]
            out.append(gone)
        else:
            need = ev[2]
            live = sorted([l for l in lots if l[0] >= day], key=lambda l: (l[2], l[0]))
            if need > sum(l[2] for l in live):
                out.append('insufficient')
                continue
            used = []
            for l in live:
                t = min(need, l[2])
                if t > 0:
                    l[2] -= t
                    need -= t
                    used.append([l[0], t])
            lots = [l for l in lots if l[2] > 0]
            out.append(used)
    return {'results': out, 'lots': lots}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['soonest expiry first', {'events': [['earn', 1, 500, 365], ['earn', 10, 300, 31], ['redeem', 20, 400]]}, {'results': [366, 41, [[41, 300], [366, 100]]], 'lots': [[366, 1, 400]]}], ['use on expiry day', {'events': [['earn', 0, 200, 30], ['redeem', 30, 151]]}, {'results': [30, [[30, 151]]], 'lots': [[30, 0, 49]]}], ['expired unusable', {'events': [['earn', 0, 200, 30], ['earn', 5, 50, 90], ['redeem', 31, 101]]}, {'results': [30, 95, 'insufficient'], 'lots': [[30, 0, 200], [95, 5, 50]]}], ['sweep reports points', {'events': [['earn', 0, 120, 10], ['earn', 0, 81, 10], ['earn', 3, 60, 100], ['sweep', 11]]}, {'results': [10, 10, 103, 201], 'lots': [[103, 3, 60]]}], ['sweep boundary', {'events': [['earn', 0, 70, 11], ['sweep', 11], ['sweep', 12]]}, {'results': [11, 0, 70], 'lots': []}], ['partial lot cleanup', {'events': [['earn', 0, 100, 50], ['earn', 1, 100, 60], ['redeem', 2, 100], ['redeem', 3, 31]]}, {'results': [50, 61, [[50, 100]], [[61, 31]]], 'lots': [[61, 1, 69]]}], ['insufficient', {'events': [['earn', 0, 100, 50], ['redeem', 1, 151], ['redeem', 2, 100]]}, {'results': [50, 'insufficient', [[50, 100]]], 'lots': []}], ['ties by earn day', {'events': [['earn', 5, 40, 20], ['earn', 1, 40, 24], ['redeem', 6, 51]]}, {'results': [25, 25, [[25, 40], [25, 11]]], 'lots': [[25, 5, 29]]}]], [['soonest expiry first', {'events': [['earn', 1, 500, 365], ['earn', 10, 300, 32], ['redeem', 20, 400]]}, {'results': [366, 42, [[42, 300], [366, 100]]], 'lots': [[366, 1, 400]]}], ['use on expiry day', {'events': [['earn', 0, 200, 30], ['redeem', 30, 152]]}, {'results': [30, [[30, 152]]], 'lots': [[30, 0, 48]]}], ['expired unusable', {'events': [['earn', 0, 200, 30], ['earn', 5, 50, 90], ['redeem', 31, 102]]}, {'results': [30, 95, 'insufficient'], 'lots': [[30, 0, 200], [95, 5, 50]]}], ['sweep reports points', {'events': [['earn', 0, 120, 10], ['earn', 0, 82, 10], ['earn', 3, 60, 100], ['sweep', 11]]}, {'results': [10, 10, 103, 202], 'lots': [[103, 3, 60]]}], ['sweep boundary', {'events': [['earn', 0, 70, 12], ['sweep', 12], ['sweep', 13]]}, {'results': [12, 0, 70], 'lots': []}], ['partial lot cleanup', {'events': [['earn', 0, 100, 50], ['earn', 1, 100, 60], ['redeem', 2, 100], ['redeem', 3, 32]]}, {'results': [50, 61, [[50, 100]], [[61, 32]]], 'lots': [[61, 1, 68]]}], ['insufficient', {'events': [['earn', 0, 100, 50], ['redeem', 1, 152], ['redeem', 2, 100]]}, {'results': [50, 'insufficient', [[50, 100]]], 'lots': []}], ['ties by earn day', {'events': [['earn', 5, 40, 20], ['earn', 1, 40, 24], ['redeem', 6, 52]]}, {'results': [25, 25, [[25, 40], [25, 12]]], 'lots': [[25, 5, 28]]}]], [['soonest expiry first', {'events': [['earn', 1, 500, 365], ['earn', 10, 300, 33], ['redeem', 20, 400]]}, {'results': [366, 43, [[43, 300], [366, 100]]], 'lots': [[366, 1, 400]]}], ['use on expiry day', {'events': [['earn', 0, 200, 30], ['redeem', 30, 153]]}, {'results': [30, [[30, 153]]], 'lots': [[30, 0, 47]]}], ['expired unusable', {'events': [['earn', 0, 200, 30], ['earn', 5, 50, 90], ['redeem', 31, 103]]}, {'results': [30, 95, 'insufficient'], 'lots': [[30, 0, 200], [95, 5, 50]]}], ['sweep reports points', {'events': [['earn', 0, 120, 10], ['earn', 0, 83, 10], ['earn', 3, 60, 100], ['sweep', 11]]}, {'results': [10, 10, 103, 203], 'lots': [[103, 3, 60]]}], ['sweep boundary', {'events': [['earn', 0, 70, 13], ['sweep', 13], ['sweep', 14]]}, {'results': [13, 0, 70], 'lots': []}], ['partial lot cleanup', {'events': [['earn', 0, 100, 50], ['earn', 1, 100, 60], ['redeem', 2, 100], ['redeem', 3, 33]]}, {'results': [50, 61, [[50, 100]], [[61, 33]]], 'lots': [[61, 1, 67]]}], ['insufficient', {'events': [['earn', 0, 100, 50], ['redeem', 1, 153], ['redeem', 2, 100]]}, {'results': [50, 'insufficient', [[50, 100]]], 'lots': []}], ['ties by earn day', {'events': [['earn', 5, 40, 20], ['earn', 1, 40, 24], ['redeem', 6, 53]]}, {'results': [25, 25, [[25, 40], [25, 13]]], 'lots': [[25, 5, 27]]}]], [['soonest expiry first', {'events': [['earn', 1, 500, 365], ['earn', 10, 300, 34], ['redeem', 20, 400]]}, {'results': [366, 44, [[44, 300], [366, 100]]], 'lots': [[366, 1, 400]]}], ['use on expiry day', {'events': [['earn', 0, 200, 30], ['redeem', 30, 154]]}, {'results': [30, [[30, 154]]], 'lots': [[30, 0, 46]]}], ['expired unusable', {'events': [['earn', 0, 200, 30], ['earn', 5, 50, 90], ['redeem', 31, 104]]}, {'results': [30, 95, 'insufficient'], 'lots': [[30, 0, 200], [95, 5, 50]]}], ['sweep reports points', {'events': [['earn', 0, 120, 10], ['earn', 0, 84, 10], ['earn', 3, 60, 100], ['sweep', 11]]}, {'results': [10, 10, 103, 204], 'lots': [[103, 3, 60]]}], ['sweep boundary', {'events': [['earn', 0, 70, 14], ['sweep', 14], ['sweep', 15]]}, {'results': [14, 0, 70], 'lots': []}], ['partial lot cleanup', {'events': [['earn', 0, 100, 50], ['earn', 1, 100, 60], ['redeem', 2, 100], ['redeem', 3, 34]]}, {'results': [50, 61, [[50, 100]], [[61, 34]]], 'lots': [[61, 1, 66]]}], ['insufficient', {'events': [['earn', 0, 100, 50], ['redeem', 1, 154], ['redeem', 2, 100]]}, {'results': [50, 'insufficient', [[50, 100]]], 'lots': []}], ['ties by earn day', {'events': [['earn', 5, 40, 20], ['earn', 1, 40, 24], ['redeem', 6, 54]]}, {'results': [25, 25, [[25, 40], [25, 14]]], 'lots': [[25, 5, 26]]}]], [['soonest expiry first', {'events': [['earn', 1, 500, 365], ['earn', 10, 300, 35], ['redeem', 20, 400]]}, {'results': [366, 45, [[45, 300], [366, 100]]], 'lots': [[366, 1, 400]]}], ['use on expiry day', {'events': [['earn', 0, 200, 30], ['redeem', 30, 155]]}, {'results': [30, [[30, 155]]], 'lots': [[30, 0, 45]]}], ['expired unusable', {'events': [['earn', 0, 200, 30], ['earn', 5, 50, 90], ['redeem', 31, 105]]}, {'results': [30, 95, 'insufficient'], 'lots': [[30, 0, 200], [95, 5, 50]]}], ['sweep reports points', {'events': [['earn', 0, 120, 10], ['earn', 0, 85, 10], ['earn', 3, 60, 100], ['sweep', 11]]}, {'results': [10, 10, 103, 205], 'lots': [[103, 3, 60]]}], ['sweep boundary', {'events': [['earn', 0, 70, 15], ['sweep', 15], ['sweep', 16]]}, {'results': [15, 0, 70], 'lots': []}], ['partial lot cleanup', {'events': [['earn', 0, 100, 50], ['earn', 1, 100, 60], ['redeem', 2, 100], ['redeem', 3, 35]]}, {'results': [50, 61, [[50, 100]], [[61, 35]]], 'lots': [[61, 1, 65]]}], ['insufficient', {'events': [['earn', 0, 100, 50], ['redeem', 1, 155], ['redeem', 2, 100]]}, {'results': [50, 'insufficient', [[50, 100]]], 'lots': []}], ['ties by earn day', {'events': [['earn', 5, 40, 20], ['earn', 1, 40, 24], ['redeem', 6, 55]]}, {'results': [25, 25, [[25, 40], [25, 15]]], 'lots': [[25, 5, 25]]}]]]
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 fixture	Actual	Expected	Outcome
soonest expiry first	`{'lots': [[366, 1, 400]], 'results': [366, 41, [[41, 300], [366, 100]]]}`	`{'lots': [[366, 1, 400]], 'results': [366, 41, [[41, 300], [366, 100]]]}`	Passed
use on expiry day	`{'lots': [[30, 0, 49]], 'results': [30, [[30, 151]]]}`	`{'lots': [[30, 0, 49]], 'results': [30, [[30, 151]]]}`	Passed
expired unusable	`{'lots': [[30, 0, 200], [95, 5, 50]], 'results': [30, 95, 'insufficient']}`	`{'lots': [[30, 0, 200], [95, 5, 50]], 'results': [30, 95, 'insufficient']}`	Passed
sweep reports points	`{'lots': [[103, 3, 60]], 'results': [10, 10, 103, 201]}`	`{'lots': [[103, 3, 60]], 'results': [10, 10, 103, 201]}`	Passed
sweep boundary	`{'lots': [], 'results': [11, 0, 70]}`	`{'lots': [], 'results': [11, 0, 70]}`	Passed
partial lot cleanup	`{'lots': [[61, 1, 69]], 'results': [50, 61, [[50, 100]], [[61, 31]]]}`	`{'lots': [[61, 1, 69]], 'results': [50, 61, [[50, 100]], [[61, 31]]]}`	Passed
insufficient	`{'lots': [], 'results': [50, 'insufficient', [[50, 100]]]}`	`{'lots': [], 'results': [50, 'insufficient', [[50, 100]]]}`	Passed
ties by earn day	`{'lots': [[25, 1, 29]], 'results': [25, 25, [[25, 40], [25, 11]]]}`	`{'lots': [[25, 5, 29]], 'results': [25, 25, [[25, 40], [25, 11]]]}`	Failed

SHA-256 / 7a12cf03c13b50de68b1244e414e6d1ce582fba0e49ccddec75bcf0a0dec48fb

3 / The verified repair

Exit 0

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

N = 1
observations = []
def solve(x):
    lots = []
    out = []
    for ev in x['events']:
        kind, day = ev[0], ev[1]
        if kind == 'earn':
            exp = day + ev[3]
            lots.append([exp, day, ev[2]])
            out.append(exp)
        elif kind == 'sweep':
            gone = sum(l[2] for l in lots if l[0] < day)
            lots = [l for l in lots if l[0] >= day]
            out.append(gone)
        else:
            need = ev[2]
            live = sorted([l for l in lots if l[0] >= day], key=lambda l: (l[0], l[1]))
            if need > sum(l[2] for l in live):
                out.append('insufficient')
                continue
            used = []
            for l in live:
                t = min(need, l[2])
                if t > 0:
                    l[2] -= t
                    need -= t
                    used.append([l[0], t])
            lots = [l for l in lots if l[2] > 0]
            out.append(used)
    return {'results': out, 'lots': lots}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['soonest expiry first', {'events': [['earn', 1, 500, 365], ['earn', 10, 300, 31], ['redeem', 20, 400]]}, {'results': [366, 41, [[41, 300], [366, 100]]], 'lots': [[366, 1, 400]]}], ['use on expiry day', {'events': [['earn', 0, 200, 30], ['redeem', 30, 151]]}, {'results': [30, [[30, 151]]], 'lots': [[30, 0, 49]]}], ['expired unusable', {'events': [['earn', 0, 200, 30], ['earn', 5, 50, 90], ['redeem', 31, 101]]}, {'results': [30, 95, 'insufficient'], 'lots': [[30, 0, 200], [95, 5, 50]]}], ['sweep reports points', {'events': [['earn', 0, 120, 10], ['earn', 0, 81, 10], ['earn', 3, 60, 100], ['sweep', 11]]}, {'results': [10, 10, 103, 201], 'lots': [[103, 3, 60]]}], ['sweep boundary', {'events': [['earn', 0, 70, 11], ['sweep', 11], ['sweep', 12]]}, {'results': [11, 0, 70], 'lots': []}], ['partial lot cleanup', {'events': [['earn', 0, 100, 50], ['earn', 1, 100, 60], ['redeem', 2, 100], ['redeem', 3, 31]]}, {'results': [50, 61, [[50, 100]], [[61, 31]]], 'lots': [[61, 1, 69]]}], ['insufficient', {'events': [['earn', 0, 100, 50], ['redeem', 1, 151], ['redeem', 2, 100]]}, {'results': [50, 'insufficient', [[50, 100]]], 'lots': []}], ['ties by earn day', {'events': [['earn', 5, 40, 20], ['earn', 1, 40, 24], ['redeem', 6, 51]]}, {'results': [25, 25, [[25, 40], [25, 11]]], 'lots': [[25, 5, 29]]}]], [['soonest expiry first', {'events': [['earn', 1, 500, 365], ['earn', 10, 300, 32], ['redeem', 20, 400]]}, {'results': [366, 42, [[42, 300], [366, 100]]], 'lots': [[366, 1, 400]]}], ['use on expiry day', {'events': [['earn', 0, 200, 30], ['redeem', 30, 152]]}, {'results': [30, [[30, 152]]], 'lots': [[30, 0, 48]]}], ['expired unusable', {'events': [['earn', 0, 200, 30], ['earn', 5, 50, 90], ['redeem', 31, 102]]}, {'results': [30, 95, 'insufficient'], 'lots': [[30, 0, 200], [95, 5, 50]]}], ['sweep reports points', {'events': [['earn', 0, 120, 10], ['earn', 0, 82, 10], ['earn', 3, 60, 100], ['sweep', 11]]}, {'results': [10, 10, 103, 202], 'lots': [[103, 3, 60]]}], ['sweep boundary', {'events': [['earn', 0, 70, 12], ['sweep', 12], ['sweep', 13]]}, {'results': [12, 0, 70], 'lots': []}], ['partial lot cleanup', {'events': [['earn', 0, 100, 50], ['earn', 1, 100, 60], ['redeem', 2, 100], ['redeem', 3, 32]]}, {'results': [50, 61, [[50, 100]], [[61, 32]]], 'lots': [[61, 1, 68]]}], ['insufficient', {'events': [['earn', 0, 100, 50], ['redeem', 1, 152], ['redeem', 2, 100]]}, {'results': [50, 'insufficient', [[50, 100]]], 'lots': []}], ['ties by earn day', {'events': [['earn', 5, 40, 20], ['earn', 1, 40, 24], ['redeem', 6, 52]]}, {'results': [25, 25, [[25, 40], [25, 12]]], 'lots': [[25, 5, 28]]}]], [['soonest expiry first', {'events': [['earn', 1, 500, 365], ['earn', 10, 300, 33], ['redeem', 20, 400]]}, {'results': [366, 43, [[43, 300], [366, 100]]], 'lots': [[366, 1, 400]]}], ['use on expiry day', {'events': [['earn', 0, 200, 30], ['redeem', 30, 153]]}, {'results': [30, [[30, 153]]], 'lots': [[30, 0, 47]]}], ['expired unusable', {'events': [['earn', 0, 200, 30], ['earn', 5, 50, 90], ['redeem', 31, 103]]}, {'results': [30, 95, 'insufficient'], 'lots': [[30, 0, 200], [95, 5, 50]]}], ['sweep reports points', {'events': [['earn', 0, 120, 10], ['earn', 0, 83, 10], ['earn', 3, 60, 100], ['sweep', 11]]}, {'results': [10, 10, 103, 203], 'lots': [[103, 3, 60]]}], ['sweep boundary', {'events': [['earn', 0, 70, 13], ['sweep', 13], ['sweep', 14]]}, {'results': [13, 0, 70], 'lots': []}], ['partial lot cleanup', {'events': [['earn', 0, 100, 50], ['earn', 1, 100, 60], ['redeem', 2, 100], ['redeem', 3, 33]]}, {'results': [50, 61, [[50, 100]], [[61, 33]]], 'lots': [[61, 1, 67]]}], ['insufficient', {'events': [['earn', 0, 100, 50], ['redeem', 1, 153], ['redeem', 2, 100]]}, {'results': [50, 'insufficient', [[50, 100]]], 'lots': []}], ['ties by earn day', {'events': [['earn', 5, 40, 20], ['earn', 1, 40, 24], ['redeem', 6, 53]]}, {'results': [25, 25, [[25, 40], [25, 13]]], 'lots': [[25, 5, 27]]}]], [['soonest expiry first', {'events': [['earn', 1, 500, 365], ['earn', 10, 300, 34], ['redeem', 20, 400]]}, {'results': [366, 44, [[44, 300], [366, 100]]], 'lots': [[366, 1, 400]]}], ['use on expiry day', {'events': [['earn', 0, 200, 30], ['redeem', 30, 154]]}, {'results': [30, [[30, 154]]], 'lots': [[30, 0, 46]]}], ['expired unusable', {'events': [['earn', 0, 200, 30], ['earn', 5, 50, 90], ['redeem', 31, 104]]}, {'results': [30, 95, 'insufficient'], 'lots': [[30, 0, 200], [95, 5, 50]]}], ['sweep reports points', {'events': [['earn', 0, 120, 10], ['earn', 0, 84, 10], ['earn', 3, 60, 100], ['sweep', 11]]}, {'results': [10, 10, 103, 204], 'lots': [[103, 3, 60]]}], ['sweep boundary', {'events': [['earn', 0, 70, 14], ['sweep', 14], ['sweep', 15]]}, {'results': [14, 0, 70], 'lots': []}], ['partial lot cleanup', {'events': [['earn', 0, 100, 50], ['earn', 1, 100, 60], ['redeem', 2, 100], ['redeem', 3, 34]]}, {'results': [50, 61, [[50, 100]], [[61, 34]]], 'lots': [[61, 1, 66]]}], ['insufficient', {'events': [['earn', 0, 100, 50], ['redeem', 1, 154], ['redeem', 2, 100]]}, {'results': [50, 'insufficient', [[50, 100]]], 'lots': []}], ['ties by earn day', {'events': [['earn', 5, 40, 20], ['earn', 1, 40, 24], ['redeem', 6, 54]]}, {'results': [25, 25, [[25, 40], [25, 14]]], 'lots': [[25, 5, 26]]}]], [['soonest expiry first', {'events': [['earn', 1, 500, 365], ['earn', 10, 300, 35], ['redeem', 20, 400]]}, {'results': [366, 45, [[45, 300], [366, 100]]], 'lots': [[366, 1, 400]]}], ['use on expiry day', {'events': [['earn', 0, 200, 30], ['redeem', 30, 155]]}, {'results': [30, [[30, 155]]], 'lots': [[30, 0, 45]]}], ['expired unusable', {'events': [['earn', 0, 200, 30], ['earn', 5, 50, 90], ['redeem', 31, 105]]}, {'results': [30, 95, 'insufficient'], 'lots': [[30, 0, 200], [95, 5, 50]]}], ['sweep reports points', {'events': [['earn', 0, 120, 10], ['earn', 0, 85, 10], ['earn', 3, 60, 100], ['sweep', 11]]}, {'results': [10, 10, 103, 205], 'lots': [[103, 3, 60]]}], ['sweep boundary', {'events': [['earn', 0, 70, 15], ['sweep', 15], ['sweep', 16]]}, {'results': [15, 0, 70], 'lots': []}], ['partial lot cleanup', {'events': [['earn', 0, 100, 50], ['earn', 1, 100, 60], ['redeem', 2, 100], ['redeem', 3, 35]]}, {'results': [50, 61, [[50, 100]], [[61, 35]]], 'lots': [[61, 1, 65]]}], ['insufficient', {'events': [['earn', 0, 100, 50], ['redeem', 1, 155], ['redeem', 2, 100]]}, {'results': [50, 'insufficient', [[50, 100]]], 'lots': []}], ['ties by earn day', {'events': [['earn', 5, 40, 20], ['earn', 1, 40, 24], ['redeem', 6, 55]]}, {'results': [25, 25, [[25, 40], [25, 15]]], 'lots': [[25, 5, 25]]}]]]
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 fixture	Actual	Expected	Outcome
soonest expiry first	`{'lots': [[366, 1, 400]], 'results': [366, 41, [[41, 300], [366, 100]]]}`	`{'lots': [[366, 1, 400]], 'results': [366, 41, [[41, 300], [366, 100]]]}`	Passed
use on expiry day	`{'lots': [[30, 0, 49]], 'results': [30, [[30, 151]]]}`	`{'lots': [[30, 0, 49]], 'results': [30, [[30, 151]]]}`	Passed
expired unusable	`{'lots': [[30, 0, 200], [95, 5, 50]], 'results': [30, 95, 'insufficient']}`	`{'lots': [[30, 0, 200], [95, 5, 50]], 'results': [30, 95, 'insufficient']}`	Passed
sweep reports points	`{'lots': [[103, 3, 60]], 'results': [10, 10, 103, 201]}`	`{'lots': [[103, 3, 60]], 'results': [10, 10, 103, 201]}`	Passed
sweep boundary	`{'lots': [], 'results': [11, 0, 70]}`	`{'lots': [], 'results': [11, 0, 70]}`	Passed
partial lot cleanup	`{'lots': [[61, 1, 69]], 'results': [50, 61, [[50, 100]], [[61, 31]]]}`	`{'lots': [[61, 1, 69]], 'results': [50, 61, [[50, 100]], [[61, 31]]]}`	Passed
insufficient	`{'lots': [], 'results': [50, 'insufficient', [[50, 100]]]}`	`{'lots': [], 'results': [50, 'insufficient', [[50, 100]]]}`	Passed
ties by earn day	`{'lots': [[25, 5, 29]], 'results': [25, 25, [[25, 40], [25, 11]]]}`	`{'lots': [[25, 5, 29]], 'results': [25, 25, [[25, 40], [25, 11]]]}`	Passed

SHA-256 / 5bc68b951670e50c9a94821866bb25d5150737754da5f6fdee108df25fde5473

Verification & scope

Stipulated bounded loyalty-program model with explicit toy rules; not any real program terms. 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 2026-09-29T14:46:45.136710+00:00.

Case digest / 29286eea18bdec40a5cf7da181c5fa8f890f892ce6284b12c7d7f016ef3cd54c