Jan 2026 OPPE 1 — archived question crops

Archived practice only. These are question-only crops from a completed January 2026 OPPE. Use them before an assessment to practise independently; do not use Learning OS or an LLM during a live OPPE. The untouched originals remain outside the deployed site; their exact source path and checksums are in the media import ledger.

1. Zigzag number grid
2. Flight tracking system
3. Group and sum by key
4. Largest zero-sum subarray
5. Move even indices to the end, reversed
6. Divisibility of the sum of the ends
7. String repeated three times