The root of all problems -> I'm not strong enough
Welcome to the algorithm template hub!
This page serves as a central navigation point for all code templates used in algorithm problem solving. Each link leads to a detailed note with explanation, usage, and recommended practice problems.
Each page includes:
This page collects links to detailed notes on all the major problem types encountered in contests, especially AtCoder. Each link leads to a page covering the topic's theory, patterns, solution techniques, and curated practice problems.
Each topic note contains:
2025-06-07| Problem | Type(s) | Data Structure / Algo | 🔥 Key Insight / Mark |
|---|---|---|---|
| D | Math | Prefix Sum | 🧠 |
| D | String | Constructive | 🧠 |
| E | Tree DP | DFS / Tree DP | 🧠🛠️ |
| F | DSU | DSU | 🌀 |
| G | Math | Fast Fourier Transform | 🌀 |
2025-05-24| Problem | Type(s) | Data Structure / Algo | 🔥 Key Insight / Mark |
|---|---|---|---|
| C | Simulation | Math | ⭐🧠🔥 |
| D | bitmask, DP | Bitmask DP | ⭐🧠🔥 |
| E | Constructive | Constructive | 🌀 |
| F | Math | 🌀 | |
| G | Graph | 🌀 |
2025-05-17| Problem | Type(s) | Data Structure / Algo | 🔥 Key Insight / Mark |
|---|---|---|---|
| C | String | Brute Force | 🌀 |
| E | Digit DP | Digit DP | 🌀 |
| F | Tree | DFS & Fenwick Tree | 🌀 |
| G | DP | DP/Fenwick Tree | 🌀 |
2025-05-10| Problem | Type(s) | Data Structure / Algo | 🔥 Key Insight / Mark |
|---|---|---|---|
| D | Multi-source BFS | Multi-source BFS | ⭐🔥 |
| E | Combination | Combination | 🧠🛠️🌀 |
| F | Interval Tree | Lowest Common Ancestor | 🌀 |
| G | square-root decomposition | Mo’s algorithm / Segment Tree | 🌀 |
2025-05-03| Problem | Type(s) | Data Structure / Algo | 🔥 Key Insight / Mark |
|---|---|---|---|
| D | bitmask, DP | bitmask / DP | ⭐🔥 |
| E | Minimum number of operations | DP | 🧠🔥 |
| F | DP | DP | 🌀 |
| G | Linear Programming | Linear Programming | 🌀 |
2025-04-27| Problem | Type(s) | Data Structure / Algo | 🔥 Key Insight / Mark |
|---|---|---|---|
| D | Maximum Independent Set on a Path | Path DP/DP | ⭐🔥 |
| E | Trie | Trie | 🌀🧠⭐🔥 |
| F | String Constructive | DP | 🌀 |
| G | Dynamic Segment Tree | Dynamic Segment Tree | 🌀 |
Extended Dijkstra refers to a class of shortest path algorithms derived from Dijkstra, adapted to problems where each node must track additional state information, such as the number of operations used, remaining power, or whether a bonus has been applied
2025-04-19| Problem | Type(s) | Data Structure / Algo | 🔥 Key Insight / Mark |
|---|---|---|---|
| D | Efficient Counting | Math | ⭐ |
| E | Expected Value Optimization | DP/Bottom-Up DP/DFS | 🔥🧠 |
| F | Path Enumeration | Meet-in-the-Middle/Bitmask | 🔥🛠️ |