2026  52

April  2

Hot100: Permutations (used[] Backtracking ACERS Guide)

April 3, 2026 · 8 min · map[name:Jeanphilo]

Hot100: Subsets (Backtracking / startIndex ACERS Guide)

April 2, 2026 · 7 min · map[name:Jeanphilo]

March  12

LeetCode 133: Clone Graph Hash Map + DFS/BFS ACERS Guide

March 19, 2026 · 11 min · map[name:Jeanphilo]

LeetCode 2089: Find Target Indices After Sorting Array ACERS Guide

March 18, 2026 · 8 min · map[name:Jeanphilo]

LeetCode 2529: Maximum Count of Positive Integer and Negative Integer ACERS Guide

March 18, 2026 · 9 min · map[name:Jeanphilo]

LeetCode 34: Find First and Last Position of Element in Sorted Array ACERS Guide

March 18, 2026 · 10 min · map[name:Jeanphilo]

LeetCode 35: Search Insert Position Lower-Bound Binary Search ACERS Guide

March 18, 2026 · 8 min · map[name:Jeanphilo]

LeetCode 744: Find Smallest Letter Greater Than Target Upper-Bound ACERS Guide

March 18, 2026 · 7 min · map[name:Jeanphilo]

Hot100: Binary Tree Level Order Traversal (BFS / DFS ACERS Guide)

March 16, 2026 · 12 min · map[name:Jeanphilo]

Hot100: Symmetric Tree (Mirror Recursion / BFS ACERS Guide)

March 16, 2026 · 11 min · map[name:Jeanphilo]

Hot100: Same Tree (Synchronous Recursion / BFS ACERS Guide)

March 16, 2026 · 11 min · map[name:Jeanphilo]

Hot100: Invert Binary Tree (Recursion / BFS ACERS Guide)

March 6, 2026 · 10 min · map[name:Jeanphilo]

Hot100: Maximum Depth of Binary Tree (DFS / BFS ACERS Guide)

March 6, 2026 · 9 min · map[name:Jeanphilo]

Hot100: Binary Tree Inorder Traversal (Recursion / Stack ACERS Guide)

March 6, 2026 · 11 min · map[name:Jeanphilo]

February  31

LeetCode 146: LRU Cache Design with O(1) Hash Map + Doubly Linked List

February 12, 2026 · 14 min · map[name:Jeanphilo]

LeetCode 19: Remove Nth Node From End of List (One-pass Two Pointers) ACERS Guide

February 12, 2026 · 12 min · map[name:Jeanphilo]

LeetCode 138: Copy List with Random Pointer — A Complete Deep-Copy Breakdown

February 11, 2026 · 12 min · map[name:Jeanphilo]

LeetCode 2: Add Two Numbers from Naive to Optimal Carry Simulation

February 11, 2026 · 14 min · map[name:Jeanphilo]

Hot100: Sort List Linked-List Merge Sort ACERS Guide

February 10, 2026 · 9 min · map[name:Jeanphilo]

Hot100: Merge K Sorted Lists Divide-and-Conquer O(N log k) ACERS Guide

February 10, 2026 · 11 min · map[name:Jeanphilo]

Hot100: Linked List Cycle II Floyd Detection + Entry Localization ACERS Guide

February 10, 2026 · 9 min · map[name:Jeanphilo]

Hot100: Merge Two Sorted Lists Sentinel Two-Pointer Merge ACERS Guide

February 10, 2026 · 10 min · map[name:Jeanphilo]

Hot100: First Missing Positive In-Place Index Placement ACERS Guide

February 10, 2026 · 10 min · map[name:Jeanphilo]

Hot100: Reverse Nodes in k-Group Group-Wise In-Place ACERS Guide

February 10, 2026 · 11 min · map[name:Jeanphilo]

Hot100: Reorder List In-Place Split-Reverse-Merge ACERS Guide

February 10, 2026 · 10 min · map[name:Jeanphilo]

Hot100: Reverse Linked List II Dummy Node + Head-Insertion ACERS Guide

February 10, 2026 · 10 min · map[name:Jeanphilo]

Hot100: Linked List Cycle Floyd Fast/Slow Pointer ACERS Guide

February 10, 2026 · 8 min · map[name:Jeanphilo]

Hot100: Palindrome Linked List Fast/Slow + Reverse Second Half O(1) Space ACERS Guide

February 9, 2026 · 10 min · map[name:Jeanphilo]

Hot100: Reverse Linked List Three-Pointer Iterative/Recursive ACERS Guide

February 9, 2026 · 9 min · map[name:Jeanphilo]

Hot100: Subarray Sum Equals K Prefix Sum + Hash Map ACERS Guide

February 9, 2026 · 9 min · map[name:Jeanphilo]

Graph Algorithms Learning Path: From BFS to Graph Computation Models

February 9, 2026 · 3 min · map[name:Jeanphilo]

Practical Graph Computation Models: How Pregel (BSP) and GAS Run PageRank/CC/Parallel BFS

February 9, 2026 · 19 min · map[name:Jeanphilo]

Graph Partitioning Algorithms: Edge-cut vs Vertex-cut and an Engineering Guide to METIS

February 9, 2026 · 18 min · map[name:Jeanphilo]

Dynamic Graphs and Incremental Computation: ACERS Guide to Incremental Shortest Path, Incremental PageRank, and Connectivity Maintenance

February 9, 2026 · 10 min · map[name:Jeanphilo]

Community Detection Primer: Engineering Trade-offs Between Louvain and Label Propagation - ACERS Analysis

February 9, 2026 · 10 min · map[name:Jeanphilo]

Subgraph Matching / Pattern Matching: VF2, Ullmann, and Engineering-Grade Pruning - ACERS Analysis

February 9, 2026 · 10 min · map[name:Jeanphilo]

The Graph Centrality Trio: Degree, Betweenness, and Closeness - ACERS Engineering Analysis

February 9, 2026 · 10 min · map[name:Jeanphilo]

PageRank / Personalized PageRank: Node Importance and Incremental Updates in Graph Databases - ACERS Analysis

February 9, 2026 · 12 min · map[name:Jeanphilo]

k-hop and Reachability Queries: BFS Limits, Reachability Indexes, and 2-hop Labeling ACERS Analysis

February 9, 2026 · 12 min · map[name:Jeanphilo]

Connected Components and Strongly Connected Components: Tarjan / Kosaraju ACERS Engineering Analysis

February 9, 2026 · 12 min · map[name:Jeanphilo]

Shortest Path Core Trio: BFS, Dijkstra, and A* ACERS Engineering Breakdown

February 9, 2026 · 15 min · map[name:Jeanphilo]

BFS / DFS Engineering Primer: k-hop Queries, Subgraph Extraction, and Path Existence ACERS Breakdown

February 9, 2026 · 15 min · map[name:Jeanphilo]

Hot100: Intersection of Two Linked Lists Two-Pointer Switch-Head O(1) Space ACERS Guide

February 9, 2026 · 12 min · map[name:Jeanphilo]

Path Sum III: Prefix Sum + Hash Map Counting Downward Paths (LeetCode 437) ACERS Guide

February 4, 2026 · 15 min · map[name:Jeanphilo]

Hot100: Spiral Matrix (Boundary Shrinking Simulation ACERS Guide)

February 3, 2026 · 13 min · map[name:Jeanphilo]

January  7

CNN, RNN, LSTM, and Transformer: Differences and When to Use Each

January 26, 2026 · 23 min · map[name:Jeanphilo]

Hot100: Trapping Rain Water (Two Pointers O(n) ACERS Guide)

January 24, 2026 · 7 min · map[name:Jeanphilo]

Hot100: Maximum Subarray (Kadane O(n) ACERS Guide)

January 23, 2026 · 7 min · map[name:Jeanphilo]

LeetCode 1437: Check If All 1’s Are at Least K Apart (ACERS Guide)

January 22, 2026 · 7 min · map[name:Jeanphilo]

LeetCode 231: Power of Two (Bit Trick O(1) ACERS Guide)

January 21, 2026 · 6 min · map[name:Jeanphilo]

LeetCode 1456: Maximum Number of Vowels in a Substring of Given Length (ACERS Guide)

January 20, 2026 · 7 min · map[name:Jeanphilo]

LeetCode 239: Sliding Window Maximum (Monotonic Queue ACERS Guide)

January 19, 2026 · 8 min · map[name:Jeanphilo]

2025  43

December  19

What Is size_t? Why C++ Loops Prefer size_t Over int

December 30, 2025 · 6 min · map[name:Jeanphilo]

LeetCode 1512: Number of Good Pairs (Hash Counting ACERS Guide)

December 30, 2025 · 5 min · map[name:Jeanphilo]

XOR and RC4: From Principles to Go Practice (with Safer Alternatives)

December 16, 2025 · 3 min · map[name:Jeanphilo]

Sorting Series (Final): Practical Selection - Choose by Scale, Stability, Memory, Distribution

December 9, 2025 · 4 min · map[name:Jeanphilo]

Do Not Let AI Drive You: Keep the Ability to Build Independently

December 8, 2025 · 3 min · map[name:Jeanphilo]

Emmet-Vim Speed Guide: Write HTML/CSS with Abbreviations

December 8, 2025 · 6 min · map[name:Jeanphilo]

Sorting Series (8): TimSort and Introsort - Engineering Patterns Behind Built-in Sorts

December 8, 2025 · 5 min · map[name:Jeanphilo]

Sorting Series (7): Non-Comparison Sorting - Counting, Bucket, Radix and the Range/Digit Tradeoff

December 7, 2025 · 5 min · map[name:Jeanphilo]

Svelte Button Configuration Guide: States, Styles, and Accessibility

December 7, 2025 · 4 min · map[name:Jeanphilo]

Sorting Series (6): Heap Sort - In-place O(n log n) with Worst-Case Guarantees

December 6, 2025 · 5 min · map[name:Jeanphilo]

Sorting Series (5): Quick Sort - Pivot Strategy, Tail Recursion, Engineering Practice

December 5, 2025 · 8 min · map[name:Jeanphilo]

LeetCode 1: Two Sum (Hash Map ACERS Summary)

December 4, 2025 · 1 min · map[name:Jeanphilo]

LeetCode 2300: Successful Pairs of Spells and Potions

December 4, 2025 · 1 min · map[name:Jeanphilo]

LeetCode 2379: Minimum Recolors to Get K Consecutive Black Blocks

December 4, 2025 · 1 min · map[name:Jeanphilo]

LeetCode 2841: Maximum Sum of Almost Unique Subarray

December 4, 2025 · 1 min · map[name:Jeanphilo]

Sorting Series (4): Merge Sort - Stable Divide and Conquer and External Sorting

December 4, 2025 · 10 min · map[name:Jeanphilo]

Sorting Series (3): Shell Sort - From Insertion to Gap-Based Efficiency

December 3, 2025 · 7 min · map[name:Jeanphilo]

Sorting Series (2): Bubble, Selection, Insertion - Three O(n^2) Baselines

December 2, 2025 · 7 min · map[name:Jeanphilo]

Sorting Series (1): How to Choose an Algorithm - Time, Space, Stability, Scenarios

December 1, 2025 · 6 min · map[name:Jeanphilo]

November  6

UFW + CrowdSec: Stop Malicious Port Scans (From Fail2ban Pain to a Modern Solution)

November 22, 2025 · 3 min · map[name:Jeanphilo]

WireGuard Full Guide: Build a Secure High-Speed Private Network (VPN Tutorial)

November 20, 2025 · 4 min · map[name:Jeanphilo]

How to Build a Blog System

November 14, 2025 · 2 min · map[name:Jeanphilo]

How to Publish with Hugo

November 14, 2025 · 2 min · map[name:Jeanphilo]

Write Clear Issues with Templates: From Zero to GitHub Issue Forms

November 11, 2025 · 7 min · map[name:Jeanphilo]

API Standards

November 6, 2025 · 3 min · map[name:Jeanphilo]

October  13

Thoughts on AI Systems

October 31, 2025 · 1 min · map[name:Jeanphilo]

How to Set Up Gitea

October 28, 2025 · 4 min · map[name:Jeanphilo]

Conventional Commits: Make Team Collaboration and Automation Efficient

October 25, 2025 · 3 min · map[name:Jeanphilo]

How to Write a Perfect Machine Learning Document

October 24, 2025 · 3 min · map[name:Jeanphilo]

Ping Works but SSH Fails: A Real Case of SSH vs VNC

October 24, 2025 · 3 min · map[name:Jeanphilo]

Run SSH Without sudo: User-Level sshd on Linux

October 24, 2025 · 4 min · map[name:Jeanphilo]

Run sshd Without sudo: Troubleshooting and Persistent User-Level SSH

October 24, 2025 · 4 min · map[name:Jeanphilo]

Auto-start frp on Ubuntu with systemd

October 23, 2025 · 3 min · map[name:Jeanphilo]

Expose WSL2 Services to the LAN via Windows Port Forwarding

October 22, 2025 · 2 min · map[name:Jeanphilo]

How to Use wrk for Load Testing

October 22, 2025 · 2 min · map[name:Jeanphilo]

LAN Git Bare on WSL2

October 22, 2025 · 2 min · map[name:Jeanphilo]

Git Branch Workflow for Small Teams

October 20, 2025 · 2 min · map[name:Jeanphilo]

Use a Local Git Bare Repo to Separate Dev and Test Environments

October 20, 2025 · 2 min · map[name:Jeanphilo]

August  5

How to Use and Configure a TypeScript Environment

August 28, 2025 · 1 min · map[name:Jeanphilo]

A New Frontend Idea for AI Assistants

August 27, 2025 · 1 min · map[name:Jeanphilo]

How to Create and Edit Mermaid Diagrams

August 26, 2025 · 1 min · map[name:Jeanphilo]

Mastering a Paper

August 26, 2025 · 3 min · map[name:Jeanphilo]

Reading an NVIDIA Paper on Small Language Models

August 26, 2025 · 1 min · map[name:Jeanphilo]