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FA-95949 / Postal address normalization / Member archive

Outward-inward postcode formatter: forbidden letters checked in the wrong positions · case 04

"ZX3 9AV" passes because only the first inward letter is tested.

Member previewVariant 4 · 3 implementations · 11 checks per implementation

Case contract

Remove all whitespace and uppercase. Length must be 5..7. The inward code is the last three characters: digit, letter, letter, where neither letter may be one of C I K M O V. The outward code is the rest: alphanumeric, starting with a letter and containing at least one digit. Return "OUTWARD INWARD" or None.

Why this case matters

Codes whose outward part varies in length must be split from the right; mis-splitting sends deliveries to the wrong sorting district.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixtureActualExpectedOutcome
lowercase forbidden inward letter"ZX6 9ZK"nullFailed

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