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FA-95786 / Shipping rate zone lookup / Open access

Ounce tiers: 16 oz priced as ounces · case 01

A parcel of exactly one pound is sold the lightweight ounce price.

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

ROOT CAUSE

The ounce/pound boundary includes 16 oz in ounce pricing.

VERIFIED REPAIR

Use ounce tiers only strictly below 16 oz.

Unsuccessful approach: Rounding before the boundary moves 15.5 oz parcels into pound pricing.

Case contract

Parcels under 16 oz are priced in ounce tiers: ounces rounded up to a whole ounce, tier = ceil(oz/4) capped at 4. 16 oz and above price by pounds = ceil(ounces/16). Zones 1 and 2 share price group 1; zone z >= 3 is group z-1. Return [kind, n, group].

Why this case matters

Lightweight services price by ounce tier before switching to pounds.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import math
N = 1
observations = []
def solve(ounces, zone):
    group = 1 if zone <= 2 else zone - 1
    if ounces <= 16:
        oz = math.ceil(ounces)
        return ['OZ', min(4, -(-oz // 4)), group]
    return ['LB', math.ceil(ounces / 16), group]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['one pound', [16, 3], ['LB', 1, 2]], ['generated mix 1', [15.99, 7], ['OZ', 4, 6]], ['small', [3.2, 2], ['OZ', 1, 1]], ['almost a pound', [15.5, 1], ['OZ', 4, 1]], ['two pounds', [32, 9], ['LB', 2, 8]], ['rounded to 13', [12.4, 4], ['OZ', 4, 3]], ['tier two', [4.2, 5], ['OZ', 2, 4]], ['generated mix 7', [33, 2], ['LB', 3, 1]]], [['generated mix 66', [16, 2], ['LB', 1, 1]], ['generated mix 37', [15.99, 2], ['OZ', 4, 1]], ['one pound', [16, 3], ['LB', 1, 2]], ['two pounds', [32, 9], ['LB', 2, 8]], ['rounded to 13', [12.4, 4], ['OZ', 4, 3]], ['tier two', [4.2, 5], ['OZ', 2, 4]], ['generated mix 8', [12.4, 5], ['OZ', 4, 4]], ['generated mix 16', [4.6, 9], ['OZ', 2, 8]]], [['generated mix 28', [16, 7], ['LB', 1, 6]], ['generated mix 63', [15.5, 1], ['OZ', 4, 1]], ['tier edge', [8, 2], ['OZ', 2, 1]], ['small', [3.2, 2], ['OZ', 1, 1]], ['almost a pound', [15.5, 1], ['OZ', 4, 1]], ['just over a pound', [17, 8], ['LB', 2, 7]], ['generated mix 19', [8, 8], ['OZ', 2, 7]], ['generated mix 27', [4.6, 6], ['OZ', 2, 5]]], [['generated mix 13', [16, 4], ['LB', 1, 3]], ['generated mix 29', [15.99, 2], ['OZ', 4, 1]], ['tier two', [4.2, 5], ['OZ', 2, 4]], ['one pound', [16, 3], ['LB', 1, 2]], ['two pounds', [32, 9], ['LB', 2, 8]], ['rounded to 13', [12.4, 4], ['OZ', 4, 3]], ['generated mix 32', [15.5, 1], ['OZ', 4, 1]], ['generated mix 40', [8, 2], ['OZ', 2, 1]]], [['one pound', [16, 3], ['LB', 1, 2]], ['generated mix 45', [15.5, 6], ['OZ', 4, 5]], ['tier edge', [8, 2], ['OZ', 2, 1]], ['small', [3.2, 2], ['OZ', 1, 1]], ['almost a pound', [15.5, 1], ['OZ', 4, 1]], ['two pounds', [32, 9], ['LB', 2, 8]], ['generated mix 42', [3.2, 7], ['OZ', 1, 6]], ['generated mix 51', [24, 6], ['LB', 2, 5]]]]
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
one pound['OZ', 4, 2]['LB', 1, 2]Failed
generated mix 1['OZ', 4, 6]['OZ', 4, 6]Passed
small['OZ', 1, 1]['OZ', 1, 1]Passed
almost a pound['OZ', 4, 1]['OZ', 4, 1]Passed
two pounds['LB', 2, 8]['LB', 2, 8]Passed
rounded to 13['OZ', 4, 3]['OZ', 4, 3]Passed
tier two['OZ', 2, 4]['OZ', 2, 4]Passed
generated mix 7['LB', 3, 1]['LB', 3, 1]Passed

SHA-256 / 73a75d83313aace98d39d9a14fe0b9208078101611f63166228052acb2922f00

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json
import math
N = 1
observations = []
def solve(ounces, zone):
    group = 1 if zone <= 2 else zone - 1
    if math.ceil(ounces) < 16:
        oz = math.ceil(ounces)
        return ['OZ', min(4, -(-oz // 4)), group]
    return ['LB', math.ceil(ounces / 16), group]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['one pound', [16, 3], ['LB', 1, 2]], ['generated mix 1', [15.99, 7], ['OZ', 4, 6]], ['small', [3.2, 2], ['OZ', 1, 1]], ['almost a pound', [15.5, 1], ['OZ', 4, 1]], ['two pounds', [32, 9], ['LB', 2, 8]], ['rounded to 13', [12.4, 4], ['OZ', 4, 3]], ['tier two', [4.2, 5], ['OZ', 2, 4]], ['generated mix 7', [33, 2], ['LB', 3, 1]]], [['generated mix 66', [16, 2], ['LB', 1, 1]], ['generated mix 37', [15.99, 2], ['OZ', 4, 1]], ['one pound', [16, 3], ['LB', 1, 2]], ['two pounds', [32, 9], ['LB', 2, 8]], ['rounded to 13', [12.4, 4], ['OZ', 4, 3]], ['tier two', [4.2, 5], ['OZ', 2, 4]], ['generated mix 8', [12.4, 5], ['OZ', 4, 4]], ['generated mix 16', [4.6, 9], ['OZ', 2, 8]]], [['generated mix 28', [16, 7], ['LB', 1, 6]], ['generated mix 63', [15.5, 1], ['OZ', 4, 1]], ['tier edge', [8, 2], ['OZ', 2, 1]], ['small', [3.2, 2], ['OZ', 1, 1]], ['almost a pound', [15.5, 1], ['OZ', 4, 1]], ['just over a pound', [17, 8], ['LB', 2, 7]], ['generated mix 19', [8, 8], ['OZ', 2, 7]], ['generated mix 27', [4.6, 6], ['OZ', 2, 5]]], [['generated mix 13', [16, 4], ['LB', 1, 3]], ['generated mix 29', [15.99, 2], ['OZ', 4, 1]], ['tier two', [4.2, 5], ['OZ', 2, 4]], ['one pound', [16, 3], ['LB', 1, 2]], ['two pounds', [32, 9], ['LB', 2, 8]], ['rounded to 13', [12.4, 4], ['OZ', 4, 3]], ['generated mix 32', [15.5, 1], ['OZ', 4, 1]], ['generated mix 40', [8, 2], ['OZ', 2, 1]]], [['one pound', [16, 3], ['LB', 1, 2]], ['generated mix 45', [15.5, 6], ['OZ', 4, 5]], ['tier edge', [8, 2], ['OZ', 2, 1]], ['small', [3.2, 2], ['OZ', 1, 1]], ['almost a pound', [15.5, 1], ['OZ', 4, 1]], ['two pounds', [32, 9], ['LB', 2, 8]], ['generated mix 42', [3.2, 7], ['OZ', 1, 6]], ['generated mix 51', [24, 6], ['LB', 2, 5]]]]
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
one pound['LB', 1, 2]['LB', 1, 2]Passed
generated mix 1['LB', 1, 6]['OZ', 4, 6]Failed
small['OZ', 1, 1]['OZ', 1, 1]Passed
almost a pound['LB', 1, 1]['OZ', 4, 1]Failed
two pounds['LB', 2, 8]['LB', 2, 8]Passed
rounded to 13['OZ', 4, 3]['OZ', 4, 3]Passed
tier two['OZ', 2, 4]['OZ', 2, 4]Passed
generated mix 7['LB', 3, 1]['LB', 3, 1]Passed

SHA-256 / 775532fe5a9d6c5ed3c308f64634b1b8c99d2f4c1ec1ad8e8ae0a38e6380b8e1

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json
import math
N = 1
observations = []
def solve(ounces, zone):
    group = 1 if zone <= 2 else zone - 1
    if ounces < 16:
        oz = math.ceil(ounces)
        return ['OZ', min(4, -(-oz // 4)), group]
    return ['LB', math.ceil(ounces / 16), group]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['one pound', [16, 3], ['LB', 1, 2]], ['generated mix 1', [15.99, 7], ['OZ', 4, 6]], ['small', [3.2, 2], ['OZ', 1, 1]], ['almost a pound', [15.5, 1], ['OZ', 4, 1]], ['two pounds', [32, 9], ['LB', 2, 8]], ['rounded to 13', [12.4, 4], ['OZ', 4, 3]], ['tier two', [4.2, 5], ['OZ', 2, 4]], ['generated mix 7', [33, 2], ['LB', 3, 1]]], [['generated mix 66', [16, 2], ['LB', 1, 1]], ['generated mix 37', [15.99, 2], ['OZ', 4, 1]], ['one pound', [16, 3], ['LB', 1, 2]], ['two pounds', [32, 9], ['LB', 2, 8]], ['rounded to 13', [12.4, 4], ['OZ', 4, 3]], ['tier two', [4.2, 5], ['OZ', 2, 4]], ['generated mix 8', [12.4, 5], ['OZ', 4, 4]], ['generated mix 16', [4.6, 9], ['OZ', 2, 8]]], [['generated mix 28', [16, 7], ['LB', 1, 6]], ['generated mix 63', [15.5, 1], ['OZ', 4, 1]], ['tier edge', [8, 2], ['OZ', 2, 1]], ['small', [3.2, 2], ['OZ', 1, 1]], ['almost a pound', [15.5, 1], ['OZ', 4, 1]], ['just over a pound', [17, 8], ['LB', 2, 7]], ['generated mix 19', [8, 8], ['OZ', 2, 7]], ['generated mix 27', [4.6, 6], ['OZ', 2, 5]]], [['generated mix 13', [16, 4], ['LB', 1, 3]], ['generated mix 29', [15.99, 2], ['OZ', 4, 1]], ['tier two', [4.2, 5], ['OZ', 2, 4]], ['one pound', [16, 3], ['LB', 1, 2]], ['two pounds', [32, 9], ['LB', 2, 8]], ['rounded to 13', [12.4, 4], ['OZ', 4, 3]], ['generated mix 32', [15.5, 1], ['OZ', 4, 1]], ['generated mix 40', [8, 2], ['OZ', 2, 1]]], [['one pound', [16, 3], ['LB', 1, 2]], ['generated mix 45', [15.5, 6], ['OZ', 4, 5]], ['tier edge', [8, 2], ['OZ', 2, 1]], ['small', [3.2, 2], ['OZ', 1, 1]], ['almost a pound', [15.5, 1], ['OZ', 4, 1]], ['two pounds', [32, 9], ['LB', 2, 8]], ['generated mix 42', [3.2, 7], ['OZ', 1, 6]], ['generated mix 51', [24, 6], ['LB', 2, 5]]]]
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
one pound['LB', 1, 2]['LB', 1, 2]Passed
generated mix 1['OZ', 4, 6]['OZ', 4, 6]Passed
small['OZ', 1, 1]['OZ', 1, 1]Passed
almost a pound['OZ', 4, 1]['OZ', 4, 1]Passed
two pounds['LB', 2, 8]['LB', 2, 8]Passed
rounded to 13['OZ', 4, 3]['OZ', 4, 3]Passed
tier two['OZ', 2, 4]['OZ', 2, 4]Passed
generated mix 7['LB', 3, 1]['LB', 3, 1]Passed

SHA-256 / 543d2ca142beac3901a6f4227c0eef86a86604d7eb215ed8d4b973686d34408f

Verification & scope

Stipulated tier sizes and zone groups. 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 2026-09-29T14:52:16.818349+00:00.

Case digest / 396750029467b7a757e798d801741c77c0dcf9ade8fabe85bb8952e8fcabb5b5