I'm a freshman majoring in Computer Science, currently growing along two main tracks:

• Competitive Programming & Algorithmic Thinking
  I use problem solving as my main training ground, focusing on C++, data structures, dynamic programming, graph algorithms, search, greedy methods, and implementation skills.

• AI-assisted Software Building
  I am also exploring how to turn ideas into usable projects with modern web technologies and AI coding tools, especially through small front-end experiments built with React and TypeScript.

This GitHub profile is my long-term technical journal: part coding archive, part blog index, part record of how I grow from solving problems to building real things.

Browser-based real-time 3D rendering and hand gesture recognition for an immersive, photo-integrated holiday experience.

Live Demo: christmas-tree-phi-seven.vercel.app
Repository: github.com/your-username/gesture-christmas-tree
Demo Video: Watch on Bilibili
Stack: React · TypeScript · Three.js · @mediapipe/hands · Zustand

Gesture 3D Christmas Tree combines real-time 3D particle rendering, AI-powered hand tracking, and photo-integrated visual storytelling. Users can upload personal images and seamlessly control the scene's state—clustering particles into a structured tree, scattering them into an exploded field, or focusing on central photos—entirely through natural hand gestures.

Browser-based whiteboard recording for teaching, technical explanation and presentation videos.

Live Demo: canvascast.nine19een.com
Repository: github.com/nine19een/CanvasCast
Demo Video: Watch on Bilibili
Stack: React · TypeScript · Vite · SVG · MediaRecorder API

CanvasCast combines whiteboard drawing, slide-based presentation, custom recording frames, camera overlay, microphone selection, teleprompter and browser-based recording output into one lightweight web app.

Video-only workflow for generating grounded lecture handouts from public course videos.

Repository: github.com/nine19een/lecture-video-handout-workflow
Stack: Python · yt-dlp · FFmpeg · Pillow · PyYAML · faster-whisper · Markdown/JSONL

Lecture Video Handout Workflow turns public lecture videos into traceable artifacts and learner-facing Chinese handouts through an agent-assisted workflow, emphasizing validation over black-box summarization.

I write technical posts about algorithm problems I have solved, focusing not only on accepted code, but also on the thinking process, mistakes, patterns, and reusable ideas behind the solution.

• 📑 蓝桥杯 2026 省赛 B 组复盘：考前状态、考场决策与赛后重做
  A post-contest review of my Lanqiao Cup 2026 Provincial Round.

• 📑 组合数学专题总结
  Modular inverse recurrence, factorial precomputation, derangements, binomial coefficients, and Catalan numbers via the reflection method.

• 📑 洛谷 P1637 / SPOJ SP2815 INCSEQ 复盘：长度 k 严格上升子序列的树状数组模板
  Layered DP and Fenwick Tree for counting increasing subsequences.

• 📑 Codeforces 1065-C1/C2 复盘：XOR 博弈与最高有效位
  XOR games and the role of the most significant bit.

• 📑 洛谷 P1133 复盘：从线性 DP 到破环成链
  From flawed linear DP to standard ring-to-chain DP.

• 📑 AtCoder ABC455-E 复盘：前缀差值统计与三集合容斥
  Prefix-difference states and inclusion-exclusion for substring counting.

➡️ Read more on my blog

I use competitive programming as my main way to train algorithmic thinking, coding stability and problem decomposition.

• 🥉 Lanqiao Cup National Third Prize, 2026
  蓝桥杯全国总决赛三等奖 · C/C++ 程序设计大学 B 组

• 🥇 Lanqiao Cup Provincial First Prize, 2026
  蓝桥杯省赛一等奖 · C/C++ 程序设计大学 B 组 · 北京赛区
  Ranked 25th in Beijing Division, approximately top 1.4% based on 179 first-prize winners.

I use online contests to test my current problem-solving ability under time pressure.

This section records my contest history across AtCoder, Codeforces, Lanqiao and other platforms.
I keep the full table here as a long-term archive of my progress, including solved count, rank, rating change and submission links when available.

📘 Full Contest History

Date	Contest	Type	TL	Solved	Rank	Performance (New Rating & Δ)	Results
2025-06-13	AtCoder Beginner Contest 462		1h 40min	4/7	4378/10763	916	View Submissions
2026-06-06	蓝桥杯全国总决赛（C/C++ 程序设计大学 B 组）		4h	---	---	National Third Prize🥉	---
2025-05-30	AtCoder Beginner Contest 460		1h 40min	3/7	4361/11116	916	View Submissions
2025-05-23	AtCoder Beginner Contest 459		1h 40min	4/7	3449/11101	911	View Submissions
2025-05-16	AtCoder Beginner Contest 458		1h 40min	5/7	1887/11082	890	View Submissions
2025-05-09	AtCoder Beginner Contest 457		1h 40min	4/7	3663/9773	802	View Submissions
2025-04-25	AtCoder Beginner Contest 455		1h 40min	4/7	3837/10243	777	View Submissions
2026-04-11	蓝桥杯省赛（C/C++ 程序设计大学 B 组，北京赛区）		4h	---	25th, approx. top 1.4%	Provincial First Prize🥇	---
2025-03-28	AtCoder Beginner Contest 451		1h 40min	4/7	3795/10775	753	View Submissions
2025-03-21	AtCoder Beginner Contest 450		1h 40min	4/7	3623/10935	713	View Submissions
2025-03-14	AtCoder Beginner Contest 449		1h 40min	3/7	6447/10836	656	View Submissions
2025-03-07	AtCoder Beginner Contest 448		1h 40min	4/7	4506/10246	674	View Submissions
2025-02-14	AtCoder Beginner Contest 445		1h 40min	3/7	3478/9306	647	View Submissions
2025-02-07	AtCoder Beginner Contest 444		1h 40min	3/7	6447/10836	583	View Submissions
2025-01-31	AtCoder Beginner Contest 443		1h 40min	4/7	3066/10067	585	View Submissions
2025-01-24	AtCoder Beginner Contest 442		1h 40min	4/7	4039/9872	458	View Submissions
2025-01-18	Codeforces Round 1074 (Div. 4)		2h 15min	4/8	6030/37011	1206	View Submissions
2026-01-17	AtCoder Beginner Contest 441		1h 40min	4/7	3974/9909	342	View Submissions
2026-01-12	AtCoder Beginner Contest 440	VP	1h 40min	2/7	---	---	View Submissions
2026-01-04	AtCoder Beginner Contest 439	VP	1h 40min	4/7	---	---	View Submissions
2025-12-30	AtCoder Beginner Contest 438	VP	1h 40min	2/7	---	---	View Submissions
2025-12-19	Codeforces Global Round 31 (Div. 1 + Div. 2)		2h 30min	2/10	7265/23426	1195	View Submissions
2025-12-13	AtCoder Beginner Contest 436		1h 40min	4/7	4345/10100	188	View Submissions
2025-12-06	AtCoder Beginner Contest 435		1h 40min	4/7	4144/9833	60	View Submissions
2025-12-05	Codeforces Round 1068 (Div. 2)		2h	2/6	6962/15806	1173	View Submissions
2025-11-28	Educational Codeforces Round 185 (Rated for Div. 2)		2h	2/6	5810/13106	1117	View Submissions
2025-11-20	Codeforces Round 1065 (Div. 3)		2h 30min	3/9	8374/24053	995	View Submissions
2025-10-17	Codeforces Round 1059 (Div. 3)		2h 15min	2/8	14812/32073	869	View Submissions
2025-10-10	Codeforces Round 1057 (Div. 2)		2h 15min	2/6	12158/19080	691	View Submissions
2025-10-10	蓝桥-全国高校新生编程排位赛-第三场		7d	5/5	47/9872	---	View Submissions
2025-10-03	Codeforces Round 1054 (Div. 3)	VP	2h 15min	3/7	---	---	View Submissions
2025-09-17	Codeforces Round 1051 (Div. 2)		2h	2/6	8712/14659	427	View Submissions
2025-08-08	Codeforces Round 1017 (Div. 4)	VP	2h 10min	3/8	---	---	View Submissions
2025-07-24	Codeforces Round 1003 (Div. 4)	VP	2h 30min	2/8	---	---	View Submissions

This is the archive of my daily problem-solving practice.
The full table is intentionally folded to keep the profile readable while preserving the complete record.

🚀 Full Coding Practice Log

Date	Problem	Difficulty	Solution
2026-06-13	AtCoder Beginner Contest 462 D - Accomplice		View Code (C++)
2026-06-13	AtCoder Beginner Contest 462 C - Not Covered Points		View Code (C++)
2026-06-13	AtCoder Beginner Contest 462 B - Gift		View Code (C++)
2026-06-13	AtCoder Beginner Contest 462 A - Secret Numbers		View Code (C++)
2026-06-04	洛谷 P12835 蓝桥星数字		View Code (C++)
2026-06-04	洛谷 P12834 项链排列		View Code (C++)
2026-05-30	AtCoder Beginner Contest 460 C - Sushi		View Code (C++)
2026-05-30	AtCoder Beginner Contest 460 B - Two Rings		View Code (C++)
2026-05-30	AtCoder Beginner Contest 460 A - Mod While Positive		View Code (C++)
2026-05-24	AtCoder Beginner Contest 459 E - Select from Subtrees		View Code (C++)
2026-05-23	AtCoder Beginner Contest 459 D - Adjacent Distinct String		View Code (C++)
2026-05-23	AtCoder Beginner Contest 459 C - Drop Blocks		View Code (C++)
2026-05-23	AtCoder Beginner Contest 459 B - 459		View Code (C++)
2026-05-23	AtCoder Beginner Contest 459 A - Hell, World!		View Code (C++)
2026-05-23	洛谷 P10495 阶乘分解		View Code (C++)
2026-05-23	洛谷 P5736 质数筛		View Code (C++)
2026-05-18	洛谷 P1754 球迷购票问题		View Code (C++)
2026-05-18	洛谷 P1641 生成字符串		View Code (C++)
2026-05-18	洛谷 P1313 计算系数		View Code (C++)
2026-05-18	洛谷 P3811 模意义下的乘法逆元		View Code (C++)
2026-05-18	洛谷 P1595 信封问题		View Code (C++)
2026-05-17	洛谷 P4071 排列计数		View Code (C++)
2026-05-17	洛谷 P2265 路边的水沟		View Code (C++)
2026-05-17	洛谷 B3717 组合数问题		View Code (C++)
2026-05-17	洛谷 B2164 组合数问题		View Code (C++)
2026-05-16	AtCoder Beginner Contest 458 E - Count 123		View Code (C++)
2026-05-16	AtCoder Beginner Contest 458 D - Chalkboard Median		View Code (C++)
2026-05-16	AtCoder Beginner Contest 458 C - C Stands for Center		View Code (C++)
2026-05-16	AtCoder Beginner Contest 458 B - Count Adjacent Cells		View Code (C++)
2026-05-16	AtCoder Beginner Contest 458 A - Chompers		View Code (C++)
2026-05-14	洛谷 P1009 阶乘之和		View Code (C++)
2026-05-11	【蓝桥 2026 省B】 H - 足球训练		View Code (C++)
2026-05-11	【蓝桥 2026 省B】 G - 理想温度		View Code (C++)
2026-05-11	【蓝桥 2026 省B】 F - 应急布线		View Code (C++)
2026-05-11	【蓝桥 2026 省B】 E - LQ 聚合		View Code (C++)
2026-05-11	【蓝桥 2026 省B】 D - 蓝桥竞技		View Code (C++)
2026-05-11	【蓝桥 2026 省B】 C - 循环右移		View Code (C++)
2026-05-11	【蓝桥 2026 省B】 B - 双碳战略		View Code (C++)
2026-05-11	【蓝桥 2026 省B】 A - 青春常数		View Code (C++)
2026-05-10	AtCoder Beginner Contest 455 E - Crossing Table Cloth		View Code (C++)
2026-05-09	AtCoder Beginner Contest 457 D - Raise Minimum		View Code (C++)
2026-05-09	AtCoder Beginner Contest 457 C - Long Sequence		View Code (C++)
2026-05-09	AtCoder Beginner Contest 457 B - Arrays		View Code (C++)
2026-05-09	AtCoder Beginner Contest 457 A - Array		View Code (C++)
2026-04-26	AtCoder Beginner Contest 455 E - Unbalanced ABC Substrings		View Code (C++)
2026-04-25	AtCoder Beginner Contest 455 D - Card Pile Query		View Code (C++)
2026-04-25	AtCoder Beginner Contest 455 C - Vanish		View Code (C++)
2026-04-25	AtCoder Beginner Contest 455 B - Spiral Galaxy		View Code (C++)
2026-04-25	AtCoder Beginner Contest 455 A - 455		View Code (C++)
2026-04-09	洛谷 P4779 单源最短路径（标准版）		View Code (C++) / View Code (C++) rewrite
2026-04-09	洛谷 P1182 数列分段 Section II		View Code (C++)
2026-04-09	洛谷 P1451 求细胞数量		View Code (C++) DFS / View Code (C++) BFS
2026-04-08	洛谷 P9243 岛屿个数		View Code (C++)
2026-04-08	洛谷 P9242 接龙数列		View Code (C++)
2026-04-08	洛谷 P9241 飞机降落		View Code (C++)
2026-04-08	洛谷 P9240 冶炼金属		View Code (C++)
2026-04-08	洛谷 P10429 拔河		View Code (C++)
2026-04-07	洛谷 P10426 宝石组合		View Code (C++)
2026-04-07	洛谷 P12134 画展布置		View Code (C++)
2026-04-05	洛谷 P12136 生产车间		View Code (C++)
2026-04-05	洛谷 P12133 产值调整		View Code (C++)
2026-04-05	洛谷 P12135 水质检测		View Code (C++)
2026-04-05	洛谷 P12132 可分解的正整数		View Code (C++)
2026-03-28	AtCoder Beginner Contest 451 D - Concat Power of 2		View Code (C++)
2026-03-28	AtCoder Beginner Contest 451 C - Understory		View Code (C++)
2026-03-28	AtCoder Beginner Contest 451 B - Personnel Change		View Code (C++)
2026-03-28	AtCoder Beginner Contest 451 A - illegal		View Code (C++)
2026-03-26	洛谷 P1379 八数码难题		View Code (C++)
2026-03-25	洛谷 P2895 Meteor Shower S		View Code (C++)
2026-03-25	洛谷 P1825 Corn Maze S		View Code (C++)
2026-03-25	洛谷 P1141 01迷宫		View Code (C++)
2026-03-25	洛谷 P1238 走迷宫		View Code (C++)
2026-03-24	洛谷 P1363 幻象迷宫		View Code (C++)
2026-03-21	AtCoder Beginner Contest 450 D - Minimize Range		View Code (C++)
2026-03-21	AtCoder Beginner Contest 450 C - Puddles		View Code (C++)
2026-03-21	AtCoder Beginner Contest 450 B - Split Ticketing		View Code (C++)
2026-03-21	AtCoder Beginner Contest 450 A - 3,2,1,GO		View Code (C++)
2026-03-21	洛谷 P1135 奇怪的电梯		View Code (C++)
2026-03-21	洛谷 P1605 迷宫		View Code (C++) / View Code (C++) rewrite
2026-03-18	洛谷 P2564 生日礼物		View Code (C++)
2026-03-18	洛谷 P1638 逛画展		View Code (C++)
2026-03-17	洛谷 P1094 纪念品分组		View Code (C++)
2026-03-14	AtCoder Beginner Contest 449 C - Comfortable Distance		View Code (C++)
2026-03-14	AtCoder Beginner Contest 449 B - Deconstruct Chocolate		View Code (C++)
2026-03-14	AtCoder Beginner Contest 449 A - π		View Code (C++)
2026-03-11	洛谷 P3174 毛毛虫		View Code (C++)
2026-03-07	AtCoder Beginner Contest 445 D - Integer-duplicated Path		View Code (C++)
2026-03-07	AtCoder Beginner Contest 448 C - Except and Min		View Code (C++)
2026-03-07	AtCoder Beginner Contest 448 B - Pepper Addiction		View Code (C++)
2026-03-07	AtCoder Beginner Contest 448 A - chmin		View Code (C++)
2026-03-04	洛谷 P3698 小Q的棋盘		View Code (C++)
2026-02-23	洛谷 P3155 叶子的染色		View Code (C++)
2026-02-22	洛谷 P1131 时态同步		View Code (C++)
2026-02-19	洛谷 P1273 有线电视网		View Code (C++)
2026-02-19	洛谷 P2014 选课		View Code (C++)
2026-02-19	AtCoder Beginner Contest 444 D - Many Repunit Sum		View Code (C++)
2026-02-14	AtCoder Beginner Contest 445 D - Reconstruct Chocolate		View Code (C++)
2026-02-14	AtCoder Beginner Contest 445 C - Sugoroku Destination		View Code (C++)
2026-02-14	AtCoder Beginner Contest 445 B - Center Alignment		View Code (C++)
2026-02-14	AtCoder Beginner Contest 445 A - Strong Word		View Code (C++)
2026-02-07	AtCoder Beginner Contest 444 C - AtCoder Riko		View Code (C++)
2026-02-07	AtCoder Beginner Contest 444 B - Digit Sum		View Code (C++)
2026-02-07	AtCoder Beginner Contest 444 A - Repdigit		View Code (C++)
2026-02-01	AtCoder Beginner Contest 443 E - Climbing Silver		View Code (C++)
2026-01-31	AtCoder Beginner Contest 443 D - Pawn Line		View Code (C++)
2026-01-31	AtCoder Beginner Contest 443 C - Chokutter Addiction		View Code (C++)
2026-01-31	AtCoder Beginner Contest 443 B - Setsubun		View Code (C++)
2026-01-31	AtCoder Beginner Contest 443 A - Append s		View Code (C++)
2026-01-30	洛谷 P2458 保安站岗		View Code (C++)
2026-01-30	洛谷 P1122 最大子树和		View Code (C++)
2026-01-30	洛谷 P1352 没有上司的舞会		View Code (C++)
2026-01-29	洛谷 P5459 回转寿司		View Code (C++)
2026-01-29	洛谷 P1610 鸿山洞的灯		View Code (C++)
2026-01-29	洛谷 P1622 释放囚犯		View Code (C++)
2026-01-29	洛谷 P1063 能量项链		View Code (C++)
2026-01-29	洛谷 P3146 248 G		View Code (C++)
2026-01-29	洛谷 P1880 石子合并		View Code (C++)
2026-01-28	洛谷 P1775 石子合并（弱化版）		View Code (C++)
2026-01-28	洛谷 P2858 Treats for the Cows G/S		View Code (C++)
2026-01-27	洛谷 P4503 企鹅 QQ		View Code (C++)
2026-01-27	洛谷 P3369 普通平衡树		View Code (C++)
2026-01-27	洛谷 P4551 最长异或路径		View Code (C++)
2026-01-26	洛谷 P8306 字典树		View Code (C++)
2026-01-26	洛谷 P3763 DNA		View Code (C++)
2026-01-25	洛谷 P2870 Best Cow Line G		View Code (C++)
2026-01-25	洛谷 P4391 Radio Transmission 无线传输		View Code (C++)
2026-01-25	洛谷 P2957 Barn Echoes G		View Code (C++)
2026-01-25	洛谷 P3370 字符串哈希		View Code (C++) / View Code (C++) review
2026-01-24	AtCoder Beginner Contest 442 D - Swap and Range Sum		View Code (C++)
2026-01-24	AtCoder Beginner Contest 442 C - Peer Review		View Code (C++)
2026-01-24	AtCoder Beginner Contest 442 B - Music Player		View Code (C++)
2026-01-24	AtCoder Beginner Contest 442 A - Count .		View Code (C++)
2026-01-24	洛谷 P3372 线段树 1		View Code (C++)
2026-01-23	洛谷 P9245 景区导游		View Code (C++)
2026-01-23	洛谷 P8805 机房		View Code (C++)
2026-01-23	洛谷 P3258 松鼠的新家		View Code (C++)
2026-01-22	洛谷 P3128 Max Flow P		View Code (C++)
2026-01-21	洛谷 P1396 营救		View Code (C++)
2026-01-21	洛谷 P1902 刺杀大使		View Code (C++)
2026-01-21	洛谷 P2440 木材加工		View Code (C++)
2026-01-21	洛谷 P4343 自动刷题机		View Code (C++)
2026-01-21	洛谷 P3853 路标设置		View Code (C++)
2026-01-21	洛谷 P1824 进击的奶牛 Aggressive Cows G		View Code (C++)
2026-01-21	洛谷 P2678 跳石头		View Code (C++)
2026-01-19	洛谷 P1160 队列安排		View Code (C++) stl链表 / View Code (C++) 数组模拟链表
2026-01-19	洛谷 P4387 验证栈序列		View Code (C++)
2026-01-19	Codeforces Round 1074 E - The Robotic Rush		View Code (C++)
2026-01-18	Codeforces Round 1074 D - OutOfMemoryError		View Code (C++)
2026-01-18	Codeforces Round 1074 C - Shifted MEX		View Code (C++)
2026-01-18	Codeforces Round 1074 B - Prefix Max		View Code (C++)
2026-01-18	Codeforces Round 1074 A - Perfect Root		View Code (C++)
2026-01-18	AtCoder Beginner Contest 441 F - Must Buy		View Code (C++)
2026-01-17	AtCoder Beginner Contest 441 E - A > B substring		View Code (C++)
2026-01-17	AtCoder Beginner Contest 441 D - Paid Walk		View Code (C++)
2026-01-17	AtCoder Beginner Contest 441 C - Sake or Water		View Code (C++)
2026-01-17	AtCoder Beginner Contest 441 B - Two Languages		View Code (C++)
2026-01-17	AtCoder Beginner Contest 441 A - Black Square		View Code (C++)
2026-01-14	洛谷 P2085 最小函数值		View Code (C++)
2026-01-14	洛谷 P1631 序列合并		View Code (C++) vis去重 / View Code (C++) 多路归并
2026-01-13	AtCoder Beginner Contest 440 E - Cookies		View Code (C++)
2026-01-13	AtCoder Beginner Contest 440 D - Forbidden List 2		View Code (C++)
2026-01-13	AtCoder Beginner Contest 440 C - Striped Horse		View Code (C++)
2026-01-12	AtCoder Beginner Contest 440 B - Trifecta		View Code (C++)
2026-01-12	AtCoder Beginner Contest 440 A - Octave		View Code (C++)
2026-01-06	洛谷 P2782 友好城市		View Code (C++)
2026-01-06	AtCoder Beginner Contest 439 E - Kite		View Code (C++)
2026-01-04	AtCoder Beginner Contest 439 D - Kadomatsu Subsequence		View Code (C++)
2026-01-04	AtCoder Beginner Contest 439 C - 2026		View Code (C++)
2026-01-04	AtCoder Beginner Contest 439 B - Happy Number		View Code (C++)
2026-01-04	AtCoder Beginner Contest 439 A - 2^n - 2*n		View Code (C++)
2026-01-03	洛谷 P4281 紧急集合 / 聚会		View Code (C++)
2026-01-03	洛谷 P3398 仓鼠找 sugar		View Code (C++)
2026-01-03	洛谷 P2912 Pasture Walking G		View Code (C++)
2026-01-02	洛谷 P3379 最近公共祖先（LCA）		View Code (C++)
2026-01-02	洛谷 P3865 ST 表 & RMQ 问题		View Code (C++) / View Code (C++) 预处理log2
2026-01-02	洛谷 P3956 棋盘		View Code (C++)
2025-12-30	AtCoder Beginner Contest 438 E - Heavy Buckets		View Code (C++)
2025-12-30	AtCoder Beginner Contest 438 D - Tail of Snake		View Code (C++)
2025-12-30	AtCoder Beginner Contest 438 C - 1D puyopuyo		View Code (C++) list / View Code (C++) stack
2025-12-30	AtCoder Beginner Contest 438 B - Substring 2		View Code (C++)
2025-12-30	AtCoder Beginner Contest 438 A - First Contest of the Year		View Code (C++)
2025-12-22	洛谷 P2149 Elaxia的路线		View Code (C++)
2025-12-22	洛谷 P1807 最长路		View Code (C++)
2025-12-21	洛谷 P2939 Revamping Trails G		View Code (C++)
2025-12-21	洛谷 P4568 飞行路线		View Code (C++)
2025-12-21	洛谷 P1462 通往奥格瑞玛的道路		View Code (C++)
2025-12-20	洛谷 P4822 冻结		View Code (C++)
2025-12-20	洛谷 P1144 最短路计数		View Code (C++)
2025-12-20	洛谷 P4779 单源最短路径（标准版）		View Code (C++)
2025-12-19	Codeforces Global Round 31 B. Ashmal		View Code (C++)
2025-12-19	Codeforces Global Round 31 A. Carnival Wheel		View Code (C++)
2025-12-16	洛谷 B3968 成绩排序		View Code (C)
2025-12-16	洛谷 P5740 最厉害的学生		View Code (C)
2025-12-14	洛谷 P1876 开灯		View Code (C++)
2025-12-13	AtCoder Beginner Contest 436 D - Teleport Maze		View Code (C++)
2025-12-13	AtCoder Beginner Contest 436 C - 2x2 Placing		View Code (C++)
2025-12-13	AtCoder Beginner Contest 436 B - Magic Square		View Code (C++)
2025-12-13	AtCoder Beginner Contest 436 A - o-padding		View Code (C++)
2025-12-12	洛谷 P1749 分饼干 II		View Code (C++)
2025-12-11	洛谷 SP2815 INCSEQ - Increasing Subsequences / Sphere INCSEQ - Increasing Subsequences		View Code (C++)
2025-12-10	洛谷 P1637 三元上升子序列		View Code (C++)
2025-12-10	洛谷 B2133 我家的门牌号		View Code (C++)
2025-12-10	洛谷 P1972 HH 的项链		View Code (C++)
2025-12-09	洛谷 P1725 琪露诺		View Code (C++)
2025-12-09	洛谷 B2131 甲流病人初筛		View Code (C++)
2025-12-09	洛谷 P1886 单调队列 / 滑动窗口		View Code (C++)
2025-12-09	洛谷 P1093 奖学金		View Code (C++)
2025-12-09	洛谷 P4305 不重复数字		View Code (C++) / View Code (C++) unordered_set
2025-12-09	洛谷 P1088 火星人		View Code (C++) DFS / View Code (C++) 全排列函数
2025-12-09	洛谷 P1449 后缀表达式		View Code (C++)
2025-12-08	洛谷 P3613 寄包柜		View Code (C++)
2025-12-08	洛谷 B2145 digit 函数		View Code (C++)
2025-12-08	洛谷 P1540 机器翻译		View Code (C++) / View Code (C++) unordered_set重写
2025-12-07	洛谷 B2146 Hermite 多项式		View Code (C++)
2025-12-07	洛谷 B2144 阿克曼（Ackermann）函数		View Code (C++)
2025-12-07	Codeforces 1068 C. Kanade's Perfect Multiples		View Code (C++)
2025-12-07	AtCoder Beginner Contest 435 E - Cover query		View Code (C++)
2025-12-06	AtCoder Beginner Contest 435 D - Reachability Query 2		View Code (C++)
2025-12-06	AtCoder Beginner Contest 435 C - Domino		View Code (C++)
2025-12-06	AtCoder Beginner Contest 435 B - No-Divisible Range		View Code (C++)
2025-12-06	AtCoder Beginner Contest 435 A - Triangular Number		View Code (C++)
2025-12-06	洛谷 CF44C Holidays / Codeforces School Team Contest 2 C. Holidays		View Code (C++)
2025-12-06	洛谷 P5057 简单题		View Code (C++)
2025-12-06	洛谷 P2068 统计和		View Code (C++)
2025-12-05	Codeforces 1068 B. Niko's Tactical Cards		View Code (C++)
2025-12-05	Codeforces 1068 A. Sleeping Through Classes		View Code (C++)
2025-12-05	洛谷 P3912 素数个数		View Code (C++)
2025-12-04	洛谷 P3383 线性筛素数		View Code (C++)
2025-12-04	洛谷 P5723 质数口袋		View Code (C++)
2025-12-03	洛谷 P1835 素数密度		View Code (C++)
2025-12-03	洛谷 B2137 判决素数个数		View Code (C++)
2025-12-02	洛谷 P5026 Lycanthropy		View Code (C++)
2025-12-02	洛谷 P4231 三步必杀		View Code (C++) 双数组 / View Code (C++) 单数组内存优化（二阶差分模板）
2025-12-02	洛谷 P1320 压缩技术（续集版）		View Code (C++)
2025-12-01	洛谷 P12526 纸牌大师		View Code (C++)
2025-11-30	洛谷 P1830 轰炸III		View Code (C++)
2025-11-29	洛谷 P1851 好朋友		View Code (C++)
2025-11-29	Codeforces(Edu) 185 C. Quotient and Remainder		View Code (C++)
2025-11-28	Codeforces(Edu) 185 B. Addition on a Segment		View Code (C++)
2025-11-28	Codeforces(Edu) 185 A. Maximum Neighborhood		View Code (C++)
2025-11-28	洛谷 P1319 压缩技术		View Code (C++)
2025-11-27	洛谷 P1204 挤牛奶 Milking Cows		View Code (C++)
2025-11-27	洛谷 P11199 ダンス / Dance		View Code (C++)
2025-11-27	洛谷 P4231 三步必杀		View Code (C++)
2025-11-26	洛谷 P1424 小鱼的航程（改进版）		View Code (C++)
2025-11-26	洛谷 P1083 借教室		View Code (C++) / View Code (C++) 重写
2025-11-25	洛谷 P1317 低洼地		View Code (C++)
2025-11-25	洛谷 P1496 火烧赤壁		View Code (C++) 排序合并区间 / View Code (C++) 离散化+差分
2025-11-24	洛谷 P1897 电梯里的尴尬		View Code (C++)
2025-11-23	洛谷 P1147 连续自然数和		View Code (C++)
2025-11-23	洛谷 P12714 A to Z		View Code (C++)
2025-11-22	洛谷 P1102 A-B 数对		View Code (C++)
2025-11-22	洛谷 P1838 三子棋I		View Code (C++)
2025-11-21	洛谷 B4061 位运算 2		View Code (C++)
2025-11-21	洛谷 B4060 位运算 1		View Code (C++)
2025-11-21	Codeforces 1059 C2. Renako Amaori and XOR Game (hard version)		View Code (C++)
2025-11-21	Codeforces 1059 C1. Renako Amaori and XOR Game (easy version)		View Code (C++)
2025-11-21	Codeforces 1065 B. Yuu Koito and Minimum Absolute Sum		View Code (C++)
2025-11-21	Codeforces 1065 A. Shizuku Hoshikawa and Farm Legs		View Code (C++)
2025-11-20	洛谷 P2196 挖地雷		View Code (C++) 线性dp / View Code (C++) 拓扑排序+dp
2025-11-20	洛谷 P1420 最长连号		View Code (C++)
2025-11-19	洛谷 B2166 查找不重复元素出现的位置		View Code (C++)
2025-11-19	洛谷 B2158 谁考了第 k 名		View Code (C++)
2025-11-17	洛谷 B2159 成绩排序		View Code (C++)
2025-11-17	洛谷 B2160 病人排队		View Code (C++)
2025-11-17	洛谷 B2125 最高分数的学生姓名		View Code (C++)
2025-11-16	洛谷 B2124 判断字符串是否为回文		View Code (C++)
2025-11-15	洛谷 B2123 字符串 p 型编码		View Code (C++)
2025-11-14	洛谷 B2122 单词翻转		View Code (C++)
2025-11-13	洛谷 B2102 计算鞍点		View Code (C++)
2025-11-13	洛谷 B2121 最长最短单词		View Code (C++)
2025-11-13	洛谷 B2120 单词的长度		View Code (C++)
2025-11-11	洛谷 B2119 删除单词后缀		View Code (C++)
2025-11-10	洛谷 B2118 验证子串		View Code (C++)
2025-11-10	洛谷 B2117 整理药名		View Code (C++)
2025-11-08	洛谷 B2116 加密的病历单		View Code (C++)
2025-11-07	洛谷 B2115 密码翻译		View Code (C++)
2025-11-06	洛谷 P1028 数的计算		View Code (C++)
2025-11-06	洛谷 B2114 配对碱基链		View Code (C)
2025-11-05	洛谷 P7113 排水系统		View Code (C++)
2025-11-05	洛谷 P1048 采药		View Code (C++) / View Code (C)
2025-11-05	洛谷 B2113 输出亲朋字符串		View Code (C)
2025-11-04	洛谷 P2834 纸币问题 3		View Code (C++) / View Code (C)
2025-11-04	洛谷 B2112 石头剪子布		View Code (C)
2025-11-04	洛谷 P2840 纸币问题 2		View Code (C++) / View Code (C)
2025-11-03	洛谷 B2111 基因相关性		View Code (C)
2025-11-02	洛谷 B2110 找第一个只出现一次的字符		View Code (C)
2025-11-02	洛谷 P1115 最大子段和		View Code (C++) / View Code (C)
2025-11-02	洛谷 P1121 环状最大两段子段和		View Code (C++)
2025-11-01	洛谷 P3156 询问学号		View Code (C)
2025-10-31	洛谷 B3637 最长上升子序列		View Code (C++) / View Code (C)
2025-10-31	洛谷 B2099 矩阵交换行		View Code (C)
2025-10-30	洛谷 B2098 整数去重		View Code (C)
2025-10-30	洛谷 P1216数字三角形 Number Triangles		View Code (C++) / View Code (C)
2025-10-29	洛谷 B4401 机器人走网格		View Code (C++)
2025-10-29	洛谷 B4289 字母组合		View Code (C)
2025-10-29	洛谷 B2093 查找特定的值		View Code (C)
2025-10-28	洛谷 P1060 开心的金明		View Code (C++)
2025-10-28	洛谷 P5724 求极差 / 最大跨度值 / 最大值和最小值的差		View Code (C)
2025-10-28	洛谷 P4414 ABC		View Code (C)
2025-10-27	洛谷 P1983 车站分级		View Code (C++)
2025-10-27	洛谷 P5719 分类平均		View Code (C)
2025-10-27	洛谷 P5722 数列求和		View Code (C)
2025-10-26	洛谷 P1046 陶陶摘苹果		View Code (C++) / View Code (C)
2025-10-26	洛谷 P2911 Bovine Bones G		View Code (C)
2025-10-26	洛谷 B2106 矩阵转置		View Code (C++) / View Code (C)
2025-10-26	洛谷 P1634 禽兽的传染病		View Code (C)
2025-10-24	洛谷 P5731 蛇形方阵		View Code (C++) / View Code (C)
2025-10-24	洛谷 B2097 最长平台		View Code (C)
2025-10-24	洛谷 P1321 单词覆盖还原		View Code (C++) / View Code (C)
2025-10-24	洛谷 P5727 冰雹猜想		View Code (C++) / View Code (C)
2025-10-24	洛谷 P1133 教主的花园		View Code (C++)
2025-10-22	洛谷 P4017 最大食物链计数		View Code (C++) DFS记忆化搜索+DP / View Code (C++) BFS拓扑排序+DP
2025-10-22	洛谷 B3644 拓扑排序 / 家谱树		View Code (C++) BFS / View Code (C++) DFS
2025-10-22	洛谷 P3916 图的遍历		View Code (C++)
2025-10-22	洛谷 P5318 查找文献		View Code (C++)
2025-10-22	洛谷 P5725 求三角形		View Code (C)
2025-10-21	洛谷 P1789 插火把		View Code (C++)
2025-10-21	洛谷 B2050 三角形判断		View Code (C++)
2025-10-20	洛谷 B2043 判断能否被 3，5，7 整除		View Code (C++)
2025-10-20	洛谷 P1152 欢乐的跳		View Code (C++)
2025-10-19	洛谷 P1614 爱与愁的心痛		View Code (C++)
2025-10-19	洛谷 P1421 小玉买文具		View Code (C++)
2025-10-19	Codeforces 1059 C. Beautiful XOR		View Code (C++)
2025-10-18	洛谷 P1548 棋盘问题		View Code (C++)
2025-10-18	洛谷 P1150 Peter 的烟		View Code (C++)
2025-10-17	Codeforces 1059 B. Beautiful String		View Code (C++)
2025-10-17	Codeforces 1059 A. Beautiful Average		View Code (C++)
2025-10-15	洛谷 P1025 数的划分		View Code (C++)
2025-10-14	洛谷 P1157 组合的输出		View Code (C++)
2025-10-14	洛谷 P1088 火星人		View Code (C++)
2025-10-13	洛谷 P1706 全排列问题		View Code (C++)
2025-10-13	洛谷 P1162 填涂颜色		View Code (C++) 由内向外BFS / View Code (C++) 由外向内BFS
2025-10-11	逆序k倍对		View Code (C++)
2025-10-11	Codeforces 1057 C. Symmetrical Polygons		View Code (C++)
2025-10-10	Codeforces 1057 B. Bitwise Reversion		View Code (C++)
2025-10-10	Codeforces 1057 A. Circle of Apple Trees		View Code (C++)
2025-10-10	蓝桥新生赛 机器人的行动轨迹		View Code (C++)
2025-10-10	蓝桥新生赛 代码纪元		View Code (C++)
2025-10-10	蓝桥新生赛 蚀光之刃		View Code (C++)
2025-10-10	蓝桥新生赛 加工等级之和		View Code (C++)
2025-10-10	蓝桥新生赛 对角线上的最值		View Code (C++)
2025-10-06	丁香花分形		View Code (C++)
2025-10-05	洛谷 P1012 拼数		View Code (C++) 手写冒泡排序 / View Code (C++) 自定义sort比较规则
2025-10-05	Codeforces 1054 D. A and B		View Code (C++)
2025-10-03	Codeforces 1054 C. MEX rose		View Code (C++)
2025-10-03	Codeforces 1054 B. Unconventional Pairs		View Code (C++)
2025-10-03	Codeforces 1054 A. Be Positive		View Code (C++)
2025-10-02	洛谷 P1012 拼数		View Code (C++)
2025-09-30	洛谷 P8613 小朋友排队		View Code (C++)
2025-09-25	洛谷 P10386 五子棋对弈		View Code (C++)
2025-09-21	洛谷 P10387 训练士兵		View Code (C++)
2025-09-18	Codeforces 1051 C. Max Tree		View Code (C++)
2025-09-17	Codeforces 1051 B. Discounts		View Code (C++)
2025-09-17	Codeforces 1051 A. All Lengths Subtraction		View Code (C++)
2025-09-17	洛谷 P1540 机器翻译		View Code (C++)
2025-09-17	洛谷 P1059 明明的随机数		View Code (C++)
2025-09-16	洛谷 P10904 挖矿		View Code (C++)
2025-09-16	洛谷 P2670 扫雷游戏		View Code (C)
2025-09-15	洛谷 P1179 数字统计		View Code (C)
2025-09-15	洛谷 P5743 猴子吃桃		View Code (C)
2025-09-14	洛谷 P1008 三连击		View Code (C++)
2025-09-14	洛谷 P10425 R 格式		View Code (C++)
2025-09-14	洛谷 P11044 食堂		View Code (C++)
2025-09-14	洛谷 P8683 后缀表达式		View Code (C++)
2025-09-12	洛谷 P8649 k 倍区间		View Code (C++)
2025-09-12	洛谷 P8680 特别数的和		View Code (C)
2025-09-11	洛谷 P11001 连连看		View Code (C++)
2025-09-11	洛谷 P8707 走方格		View Code (C++)
2025-09-11	洛谷 P10910 最小字符串		View Code (C++)
2025-09-09	洛谷 P12156 电池分组		View Code (C++)
2025-09-09	洛谷 P13894 填充		View Code (C++)
2025-09-08	洛谷 P13876 特殊日期		View Code (C++)
2025-09-08	洛谷 P13878 平均		View Code (C++)
2025-09-07	洛谷 P13887 三国游戏		View Code (C++)
2025-09-07	洛谷 P13930 字符统计		View Code (C++)
2025-09-06	洛谷 P10903 商品库存管理		View Code (C++)
2025-09-05	洛谷 P12085 整数删除		View Code (C++)
2025-09-05	洛谷 P12288 栈		View Code (C++)
2025-09-02	洛谷 P6033 合并果子 加强版		View Code (C++)
2025-09-02	洛谷 P1090 合并果子		View Code (C++)
2025-08-29	洛谷 P8673 迷宫与陷阱		View Code (C++)
2025-08-25	洛谷 P1443 马的遍历		View Code (C++)
2025-08-24	洛谷 B3631 单向链表		View Code (C++)
2025-08-24	洛谷 P11042 类斐波那契循环数		View Code (C++)
2025-08-24	洛谷 P1996 约瑟夫问题		View Code (C++)
2025-08-23	洛谷 P10901 封闭图形个数		View Code (C++)
2025-08-23	洛谷 P12162 数位倍数		View Code (C++)
2025-08-23	洛谷 P12163 2025		View Code (C++)
2025-08-23	洛谷 P12164 2025 图形		View Code (C++)
2025-08-23	洛谷 P1440 求m区间内的最小值		View Code (C++)
2025-08-23	洛谷 P1890 gcd区间		View Code (C++)
2025-08-23	洛谷 P2251 质量检测		View Code (C++)
2025-08-23	洛谷 P3865 ST 表 & RMQ 问题		View Code (C++)
2025-08-22	洛谷 P10900 数字诗意		View Code (C++)
2025-08-21	洛谷 P12280 特别的数组		View Code (C++)
2025-08-20	洛谷 P1381 单词背诵		View Code (C++)
2025-08-20	洛谷 P5266 学籍管理		View Code (C++)
2025-08-20	洛谷 P8630 密文搜索		View Code (C++)
2025-08-19	洛谷 P3370 字符串哈希		View Code (C++)
2025-08-19	洛谷 P3879 阅读理解		View Code (C++)
2025-08-19	洛谷 P4305 不重复数字		View Code (C++)
2025-08-17	洛谷 P2357 守墓人		View Code (C++)
2025-08-17	洛谷 P3397 地毯		View Code (C++)
2025-08-16	洛谷 P1833 樱花		View Code (C++)
2025-08-16	洛谷 P1941 飞扬的小鸟		View Code (C++)
2025-08-16	洛谷 P2367 语文成绩		View Code (C++)
2025-08-13	洛谷 P1776 宝物筛选		View Code (C++)
2025-08-12	洛谷 P10497 Lost Cows		View Code (C++)
2025-08-12	洛谷 P1908 逆序对		View Code (C++)
2025-08-12	洛谷 P3368 树状数组 2		View Code (C++)
2025-08-12	洛谷 P3374 树状数组 1		View Code (C++)
2025-08-10	Codeforces Round 1017 F. Trulimero Trulicina		View Code (C++)
2025-08-09	Codeforces Round 1017 E. Boneca Ambalabu		View Code (C++)
2025-08-08	Codeforces Round 1017 D. Tung Tung Sahur		View Code (C++)
2025-08-07	洛谷 P1083 借教室		View Code (C++)
2025-08-07	Codeforces Round 1017 C. Brr Brrr Patapim		View Code (C++)
2025-08-07	Codeforces Round 1017 B. Bobritto Bandito		View Code (C++)
2025-08-07	Codeforces Round 1017 A. Trippi Troppi		View Code (C++)
2025-08-06	洛谷 P1064 金明的预算方案		View Code (C++)
2025-08-05	洛谷 P3842 线段		View Code (C++)
2025-08-04	洛谷 P1077 摆花		View Code (C++)
2025-08-04	洛谷 P2392 kkksc03考前临时抱佛脚		View Code (C++)
2025-08-01	洛谷 P1164 小A点菜		View Code (C++)
2025-07-31	洛谷 P1049 装箱问题		View Code (C++)
2025-07-31	洛谷 P1616 疯狂的采药		View Code (C++)
2025-07-29	洛谷 P1002 过河卒		View Code (C++)
2025-07-29	洛谷 P1802 5 倍经验日		View Code (C++)
2025-07-28	洛谷 P1115 最大子段和		View Code (C++)
2025-07-28	洛谷 P1434 滑雪		View Code (C++)
2025-07-28	洛谷 P4017 最大食物链计数		View Code (C++)
2025-07-27	Codeforces Round 1003 D. Skibidus and Sigma		View Code (C++)
2025-07-24	Codeforces Round 1003 C2. Skibidus and Fanum Tax (hard version)		View Code (C++)
2025-07-24	Codeforces Round 1003 B. Skibidus and Ohio		View Code (C++)
2025-07-24	Codeforces Round 1003 A. Skibidus and Amog'u		View Code (C++)
2025-07-23	洛谷 P2196 挖地雷		View Code (C++)
2025-07-22	洛谷 P1067 多项式输出		View Code (C++)
2025-07-22	洛谷 P1328 生活大爆炸版石头剪刀布		View Code (C++)
2025-07-21	洛谷 P1048 采药		View Code (C++)
2025-07-21	洛谷 P1143 进制转换		View Code (C++)
2025-07-19	洛谷 P2834 纸币问题 3		View Code (C++)
2025-07-19	洛谷 P2840 纸币问题 2		View Code (C++)
2025-07-18	洛谷 P4924 魔法少女小Scarlet		View Code (C++)
2025-07-17	洛谷 P1036 选数		View Code (C++)
2025-07-17	洛谷 P1219 八皇后 Checker Challenge		View Code (C++)
2025-07-17	洛谷 P1605 迷宫		View Code (C++)
2025-07-16	洛谷 B2108 图像模糊处理		View Code (C++)
2025-07-16	洛谷 P1678 烦恼的高考志愿		View Code (C++)
2025-07-16	洛谷 P2141 珠心算测验		View Code (C++)
2025-07-16	洛谷 P2550 彩票摇奖		View Code (C++)
2025-07-16	洛谷 P5734 文字处理软件		View Code (C++)
2025-07-15	洛谷 P10424 好数		View Code (C++)
2025-07-15	洛谷 P1047 校门外的树		View Code (C++)
2025-07-15	洛谷 P1596 Lake Counting S		View Code (C++)
2025-07-15	洛谷 P1957 口算练习题		View Code (C++)
2025-07-14	opj 1750 全排列		View Code (C++)
2025-07-14	opj 6264 走出迷宫		View Code (C++)
2025-07-13	洛谷 P1055 ISBN 号码		View Code (C++)
2025-07-12	洛谷 P1699 Bucket Brigade B		View Code (C++)
2025-07-12	洛谷 P2615 神奇的幻方		View Code (C++)
2025-07-12	洛谷 P9974 Candy Cane Feast B		View Code (C++)
2025-07-12	opj 6261 汉诺塔问题		View Code (C++)
2025-07-12	opj 1755 菲波那契数列		View Code (C++)
2025-07-11	洛谷 P1226 快速幂		View Code (C++)
2025-07-11	洛谷 P1308 统计单词数		View Code (C++)
2025-07-11	洛谷 P2249 查找		View Code (C++)
2025-07-10	洛谷 P1031 均分纸牌		View Code (C++)
2025-07-09	洛谷 P1125 笨小猴		View Code (C++)
2025-07-08	洛谷 P2842 纸币问题 1		View Code (C++)
2025-07-08	洛谷 P3741 小果的键盘		View Code (C++)
2025-07-07	洛谷 P1200 你的飞碟在这儿 Your Ride Is Here		View Code (C++)
2025-07-07	洛谷 P1216 数字三角形 Number Triangles		View Code (C++)
2025-07-07	洛谷 P1597 语句解析		View Code (C++)
2025-07-07	洛谷 P1765 手机		View Code (C++)
2025-07-06	洛谷 B3637 最长上升子序列		View Code (C++)
2025-07-04	洛谷 P1321 单词覆盖还原		View Code (C++)
2025-07-04	洛谷 P1554 梦中的统计		View Code (C++)
2025-07-04	洛谷 P5015 标题统计		View Code (C++)
2025-07-04	洛谷 P5733 自动修正		View Code (C++)
2025-07-03	洛谷 B2105 矩阵乘法		View Code (C++)
2025-07-03	洛谷 B2106 矩阵转置		View Code (C++)
2025-07-03	洛谷 B2107 图像旋转		View Code (C++)
2025-07-03	洛谷 P1085 不高兴的津津		View Code (C++)
2025-07-03	洛谷 P1427 小鱼的数字游戏		View Code (C++)
2025-07-03	洛谷 P1428 小鱼比可爱		View Code (C++)
2025-07-03	洛谷 P1914 小书童——凯撒密码		View Code (C++)
2025-07-03	洛谷 P5727 冰雹猜想		View Code (C++)
2025-07-03	洛谷 P5728 旗鼓相当的对手		View Code (C++)
2025-07-03	洛谷 P5731 蛇形方阵		View Code (C++)
2025-07-02	洛谷 B2002 Hello,World!		View Code (C++)
2025-07-02	洛谷 B2025 输出字符菱形		View Code (C++)
2025-07-02	洛谷 P1000 超级玛丽游戏		View Code (C++)
2025-07-02	洛谷 P1001 A+B Problem		View Code (C++)
2025-07-02	洛谷 P1046 陶陶摘苹果		View Code (C++)
2025-07-02	洛谷 P1425 小鱼的游泳时间		View Code (C++)
2025-07-02	洛谷 P5711 闰年判断		View Code (C++)
2025-07-02	洛谷 P5720 一尺之棰		View Code (C++)
2025-07-02	洛谷 P5721 数字直角三角形		View Code (C++)

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