2026
7 posts
- →AtCoder Solutions 1: Number Theory, Binary Search, and Representation
March-June 2024, primarily based on original solution records, including ABC 340 F, 341 D, 346 D/E/F, 356 D/E/F.
- →AtCoder Solutions 2: DP, Probability, Graphs, and Data Structures
April~July 2024, primarily based on original solution records, including ABC 348 E/F, 350 D/E, 351 D/E/F, 357 D/E/F, 358 C/E/G, 360 E.
- →Codeforces Solutions 1: Construction, Bit Operations, and Greedy
Solutions from Jan-Jul 2024, focusing on construction, bit operations, and greedy problems from Codeforces.
- →Codeforces Solutions 2: Prefix Sums, Strings, and Thought Transformation
Solutions from Dec 2023 to Jul 2024, covering prefix sums, strings, and transformation-oriented Codeforces problems.
- →Codeforces Solutions 3: Number Theory, Games, Combinatorics, and EDU
Solutions from Jan-Sep 2024, focusing on number theory, game theory, combinatorics, and EDU problems from Codeforces.
- →Invitational and Addendum: Zhengzhou, Kunming, HDU, and Luogu
Primarily based on original solution records, including Zhengzhou Invitational, Kunming Invitational, HDU 2973, and Luogu B3645.
- →Nowcoder Solutions: Winter Contests, Weeklies, and Multi-School
December 2023 to August 2024, primarily based on original solution records, covering bookmarked winter contests, weekly contests, and multi-school problems.
2025
12 posts
- →Tips to improve concentration
Mindfulness, cognitive training, and a healthy lifestyle may help sharpen your focus.
- →Redis Is More Than Cache: Locks, Queues, and HyperLogLog
Based on original Redis notes, covering distributed locks, message queues, HyperLogLog, and high availability.
- →Redis Knowledge Notes
Redis-related notes previously written in Apple Notes
- →How MySQL Preserves Consistency: Transactions, Locks, MVCC, and Logs
Previously recorded content about MySQL in Apple Notes
- →MySQL Logs and Locking Mechanisms
Earlier MySQL notes originally written in Apple Notes.
- →When Problem-Setting Syndrome Strikes, Start with the Strange Core
Based on the original "Problem-Setting Syndrome Struck" notes, preserving the "Magic Bag" problem, derivation, code, and extension directions.
- →Concurrency Is Not Just Threads: From JMM to Thread Pools and CompletableFuture
Based on original Java concurrency notes, covering JMM, locks, atomic classes, ThreadLocal, thread pools, and more.
- →Why MySQL Is Fast: Pages, Indexes, and B+ Trees
Based on the original MySQL notes, this post covers fundamentals, indexes, B+ trees, and execution plans.
- →Why Redis Fits Caching: Data Structures, Thread Model, and Persistence
Based on original Redis notes and Apple Notes, covering cache positioning, data structures, thread model, and persistence fundamentals.
- →Java Abstract Boundaries: Collections, IO, Reflection, Proxy, and SPI
Based on original Java notes, preserving the original organization of Collections, IO, Reflection, Proxy, and SPI.
- →How Operating Systems Hold Up Programs: Processes, Memory, Files, and I/O
A practical review of operating systems: processes, threads, virtual memory, page cache, system calls, file systems, and I/O.
- →From Browser to Server: Which Network Layers a Request Crosses
Don't reduce computer networks to a list of protocol names. Follow a real request and see how DNS, TCP, TLS, HTTP, and congestion control work together.
2024
5 posts
- →Why Polynomial Algorithms Matter in Competitive Programming
From convolution, point-value representation, FFT/NTT to formal power series - understanding what this polynomial toolkit is really solving.
- →From Convolution to Inversion: What Mobius Inversion Does
Based on original number theory notes, covering Dirichlet convolution, Möbius function, inversion techniques, and common identities.
- →My Intro to Generating Functions: Let Coefficients Be Answers
Built from the original notes, restoring ordinary generating functions, exponential generating functions, modeling intuition, and several typical problems.
- →A Framework for Judging Game Theory in Contests
Based on original game theory notes, supplementing the judgment framework, Bash/Nim, Misere games, Fibonacci game, Wythoff's game, and SG function.
- →Search Is Not Brute Force: DFS, BFS, and DP
Built from original search problem sets and solution notes, organizing DFS, BFS, pruning, shortest paths, and state-space search.
2023
2 posts
- →Sieve Methods Beyond Primes: A Unified View of Linear Sieve
Based on original number theory notes, covering prime sieves, Euler's totient function, and Wilson's theorem.
- →From Divisibility to Congruence: Number Theory Basics
Based on original number theory notes, covering gcd, lcm, Bezout, exgcd, fast power, modular inverse, and CRT.