Blogs and Newsletters¶

Written resources compound differently than videos: you can search them, reference them mid-solve, and return to specific paragraphs. The communities below produce writing worth bookmarking. The rule here is the same as for everything else — one primary reference per topic, supplements only when the primary fails.

Codeforces Blogs¶

The Codeforces blog section (codeforces.com/blog) is the highest-density technical writing on competitive programming available anywhere for free. It is not a newsletter — it is a living, community-maintained encyclopedia of algorithmic techniques. The problem is discoverability: quality ranges from expert-level to wrong.

How to find the best Codeforces blogs:

The “Educational” tag filter: On codeforces.com/blog, filter by “Educational” tag. These are community-vetted tutorial posts.
Google as the search engine: Do not use Codeforces’s internal search for tutorials. Use:
```
site:codeforces.com/blog [topic]
```
e.g., site:codeforces.com/blog segment tree lazy propagation tutorial
The master resource list: Bookmark this — it is maintained by the Codeforces community and lists the best tutorial blogs by topic:
- codeforces.com/blog/entry/62690 (A Codeforces Blog of Blogs — community-curated)
- codeforces.com/blog/entry/13529 (Codeforces problem categories by tag)
Post-contest editorials: After every CF contest (Div. 3, Div. 2, Educational Rounds), the official editorial appears as a blog post. These are the most valuable regular reading. Go to the contest page → “Editorial” link.

Quality calibration for CF blogs:

High trust: Blogs by red or orange-rated users. Blogs with 200+ upvotes. Official contest editorials.
Medium trust: Blogs by purple/blue users with 50+ upvotes. Cross-reference before implementing.
Low trust: New accounts, low-rated users, posts with <10 upvotes. May contain errors. Verify against CP-Algorithms.com before using.

CP-Algorithms.com ¶

URL: cp-algorithms.com
Maintenance status: Actively maintained as of 2025-2026. Community contributions via GitHub (github.com/cp-algorithms/cp-algorithms). Last update checks show commits in 2025.
What it is: A curated collection of algorithm explanations with proofs, complexity analysis, and code implementations in C++. The closest thing to a free textbook for competitive programming that is also practically current.
Quality: High. Editorial review process. Code examples are correct and well-explained.

Sections to bookmark by phase:

Phase	CP-Algorithms Sections to Bookmark
Phase 0–1	/algebra/sieve-of-eratosthenes, /algebra/binary-exp, /data_structures/stack_queue_modification
Phase 2	/data_structures/segment_tree, /data_structures/fenwick, /graph/depth-first-search, /graph/breadth-first-search
Phase 3	/graph/dijkstra, /graph/bellman_ford, /graph/floyd-warshall, /graph/mst_kruskal, /graph/topological-sort, /graph/strongly-connected-components
Phase 4	/dynamic_programming/intro-to-dp (start here), /dynamic_programming/knapsack
Phase 5	/string/prefix-function, /string/z-function, /string/suffix-array, /data_structures/segment_tree (lazy propagation section)

How to use it: CP-Algorithms is a reference, not a course. Read the section → close the page → implement the algorithm from scratch → verify against the page. Never copy-paste from it.

USACO Guide¶

URL: usaco.guide
Maintenance status: Actively maintained, community-contributed. Activity visible on GitHub (github.com/cpinitiative/usaco-guide). Regular commits in 2025.
What it is: A structured curriculum for competitive programming, organized by USACO contest levels (Bronze → Silver → Gold → Platinum). Each section has: concept explanation, code template, and curated practice problems (mostly from CSES, CF, and USACO itself).
Primary audience: USACO competitors (mostly high school). But the content is excellent for any CP beginner through intermediate.
For this learner: Use as a structured curriculum reference for CP phases. You don’t need to do USACO contests to use this.

How to navigate:

Bronze level (usaco.guide/bronze): Sorting, greedy, basic simulation — corresponds to CF 800–1200 difficulty
Silver level (usaco.guide/silver): Two pointers, binary search on answer, trees, graph traversal — corresponds to CF 1200–1600
Gold level (usaco.guide/gold): Segment trees, advanced DP, SCC, max flow — corresponds to CF 1800–2200
Platinum level: Expert-level, beyond the scope of this 9-month plan

For this learner’s 9-month plan:

Phase 2–3: USACO Bronze + Silver sections for structured problem lists
Phase 5: USACO Gold for advanced data structures

Competitive Programmer’s Handbook — Community Discussion¶

URL for free PDF: cses.fi/book/book.pdf (direct link to Antti Laaksonen’s PDF)
Community sentiment: Consistent praise on r/competitiveprogramming and r/learnprogramming. Described as “the best free book for learning CP from scratch.” The PDF is 300 pages and covers most algorithmic topics at Silver–Gold USACO level.
Is it maintained? The PDF is a fixed document (2022 version is the latest as of 2026). It does not update like CP-Algorithms.com. This is fine — the algorithms don’t change.
Community thread evidence: Multiple r/learnprogramming threads (2024–2025) recommend it as the first book to read before CLRS. “Read CPH before CLRS. CLRS without CPH is torture.”

Newsletters¶

The competitive programming space does not have high-quality newsletters in the traditional sense (weekly email digest). What exists instead:

LeetCode Weekly Digest¶

LeetCode sends contest summaries and new problem notifications if you opt in. Not educational content. Skip unless you want contest reminders.

USACO Mailing List¶

usaco.org has a mailing list for contest announcements. Only relevant if you plan to do USACO contests specifically (pre-college focus, but adult learners can participate).

LeetCode Editorial Quality¶

LeetCode provides official editorials for most problems (accessible with and without Premium).

Verdict (2025–2026 community assessment):

Quality varies significantly by problem age. Problems added before 2020 have older-style editorials that skip implementation details. Problems from 2021 onward generally have better editorials.
Premium vs. free: Some editorial content is behind Premium. Free users get the editorial for most problems but may miss the “follow-up” optimal solution explanation.
Better alternatives for editorials:
1. LeetCode Discuss tab (community solutions) — search for solutions with highest upvotes + clean code
2. NeetCode video (for NeetCode 150 problems specifically)
3. Striver video (for A2Z sheet problems)
When to read LeetCode editorials: After you’ve already solved a problem and want to see if there’s a more elegant approach. Not as primary explanation source.

GeeksForGeeks — Use With Caution¶

GFG appears in almost every Google search for DSA topics. The quality is inconsistent.

Problem: GFG articles are often outdated, sometimes have incorrect code, and rarely cite algorithmic proofs or complexity analysis correctly.
Where GFG is acceptable: Looking up basic definitions (what is a trie, what is a red-black tree) to get the vocabulary before going to a higher-quality source.
Where GFG fails: Algorithm implementations, complexity proofs, interview tips. Do not trust GFG code without verifying against CP-Algorithms.com or a vetted CF blog.
Community verdict (r/learnprogramming, 2025): “GFG is like the Wikipedia of CS — good for getting an overview, terrible as a primary source for implementation.”

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