# Project Learnings

> Auto-maintained by the self-improve skill. Read at session start, updated at session end.

## Patterns That Work
<!-- Approaches that produced good results -->

## Mistakes to Avoid
<!-- Failed approaches and why they failed -->

## Codebase Conventions

**[2026-05-04] — File organization**
- Observation: Most flashcard files are flat in `org/cpp/`, but subdirectories exist (`tricks/`, `dsa/`) for topic grouping. AGENTS.md only documents the flat convention.
- Action: When creating new cards, use flat `org/cpp/topic.org` for STL/language features; subdirectories for broader categories (DSA, tricks). Propose updating AGENTS.md if this solidifies.
- Confidence: medium

**[2026-05-04] — Card format variance**
- Observation: `org/cpp/dsa/udfs.org` uses raw `#+title:` + code blocks without ANKI properties. `org/cpp/ufds.org` follows the proper Anki card format. The proper format (with ANKI_NOTE_TYPE, Front/Back sections) is what gets exported.
- Action: Always use the full Anki card format from AGENTS.md when creating flashcards. Raw code files in dsa/ may be scratch/reference, not export-ready cards.
- Confidence: medium

**[2026-05-04] — Naming: UFDS not UDFS**
- Observation: `org/cpp/dsa/udfs.org` is a typo — the data structure is "Union-Find Disjoint Set" = UFDS. The properly-formatted file `org/cpp/ufds.org` uses the correct name.
- Action: Use "ufds" spelling. The dsa/udfs.org appears to be an earlier draft.
- Confidence: high

## Environment & Config

**[2026-05-04] — Git state**
- Observation: Single branch `master` with remote `origin/master`. No branching workflow — commits go directly to master.
- Action: Commit directly to master. Push when work is complete.
- Confidence: high

## Business Context

**[2026-05-04] — Study focus**
- Observation: Recent commits cover STL containers (deque, array, set, map, iterators) and DSA (UFDS). Inbox has LeetCode solutions (two sum, max consecutive ones) with notes to learn binary search and `using` keyword.
- Action: Current study trajectory is STL containers + competitive programming DSA. Prioritize cards for these topics.
- Confidence: high

## Open Questions

**[2026-05-04] — Duplicate UFDS files**
- Question: Are both `org/cpp/ufds.org` (402 lines, proper format) and `org/cpp/dsa/udfs.org` (41 lines, raw code) needed? The former seems to supersede the latter.
- Action: Ask user if `dsa/udfs.org` should be removed or merged.