You signed in with another tab or window. Reload to refresh your session.You signed out in another tab or window. Reload to refresh your session.You switched accounts on another tab or window. Reload to refresh your session.Dismiss alert
{{ message }}
Repository navigation
Line Up Exercise - Missing test case for ordinal suffix,multiples of 11/12/13 outside the teens range are not covered #1647
The test suite for line-up does not include any numbers whose last two digits are a multiple of 11, 12, or 13 outside the 11–13 range itself (e.g. 22, 24, 33, 36, 44, 52, 60, 63, 65, 72, 78, 91, 96...).
This gap allows an incorrect implementation to pass. For example, a common bug is checking divisibility instead of range when handling the "teens" exception:
This looks like it's meant to handle the 11th/12th/13th exception (and does, since 11%11=0, 12%12=0, 13%13=0), but it also incorrectly catches any other multiple of 11, 12, or 13 — such as 22, 33, 44, 52, 91 — and returns "th" for them instead of the correct "nd"/"rd"/"st".
Expected behavior
22 → "22nd" (a buggy implementation using the check above would produce "22th")
33 → "33rd"
52 → "52nd"
91 → "91st"
Suggested fix
Add at least one test case per suffix category (1st/2nd/3rd/4th-equivalents) that is also a multiple of 11, 12, or 13, to catch this class of bug (e.g. 22, 33, 52, 91.)
If line-up has canonical data in problem-specifications, it may be worth raising there too, since it's shared across tracks.
At Exercism we use our Community Forum, not GitHub issues, as the primary place for discussion. That allows maintainers and contributors from across Exercism's ecosystem to discuss your problems/ideas/suggestions without them having to subscribe to hundreds of repositories.
This issue will be automatically closed. Please use this link to copy your GitHub Issue into a new topic on the forum, where we look forward to chatting with you!
If you're interested in learning more about this auto-responder, please read this blog post.
Activity
github-actions commentedon Jul 25, 2026
Hello. Thanks for opening an issue on Exercism 🙂
At Exercism we use our Community Forum, not GitHub issues, as the primary place for discussion. That allows maintainers and contributors from across Exercism's ecosystem to discuss your problems/ideas/suggestions without them having to subscribe to hundreds of repositories.
This issue will be automatically closed. Please use this link to copy your GitHub Issue into a new topic on the forum, where we look forward to chatting with you!
If you're interested in learning more about this auto-responder, please read this blog post.
SleeplessByte commentedon Jul 26, 2026
@QuentinNev Thanks for your report. The correct approach here would be to raise it there indeed.