🏆 XCPC

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A comprehensive competitive programming solution & template repository for ICPC / CCPC / LanQiao Cup / GPLT and more.

Organized by platform, contest, and topic — featuring 4,200+ solutions and 45 curated algorithm templates for review, retrieval, and reuse.

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📊 Overview

Metric	Value
📝 Total Solutions	4,232
📂 Total Directories	1,038
🏟️ Platforms Covered	10+
📐 Algorithm Templates	45
🏅 VP Contests	133
🔥 CF Contests	195

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📁 Project Structure

XCPC/
├── 00 Codeforces/          # CF contest solutions (195 contests / 1050 problems)
├── 01 Atcoder/             # AtCoder contest solutions (21 contests / 109 problems)
├── 02 Luogu/               # Luogu topic-based training (208 problems)
├── 03 Nowcoder/            # Nowcoder contests & training (756 problems)
├── 04 HDU/                 # HDU / Dingba Programming (247 problems)
├── 05 PTA/                 # PTA / GPLT / RuiKang (559 problems)
├── 06 Virtual participation/ # ICPC/CCPC VP training (133 contests / 806 problems)
├── 07 码蹄集/               # Matiji Cup / Baidu Star (170 problems)
├── 08 蓝桥云/               # LanQiao Cup Provincial & National (187 problems)
├── 09 Advanced Guide.../   # "Advanced Guide to Algorithm Competitions" (16 problems)
├── 10 C++ with STL/        # STL topic exercises (74 problems)
├── 11 Pre-NOI Check/       # NOI pre-check exercises (5 problems)
└── 12 XCPC模板/            # Algorithm templates (45 templates)

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🔍 Platform Breakdown

🟣 Codeforces — 1,050 Problems / 195 Contests

Covering Round 790 – 1072, Edu 121 – 181, and more.

Contest Type	Count	Description
Div.2	72	Primary competition level
Div.3	54	Foundational training
Educational	31	Educational rounds
Div.4	19	Beginner level
Div.1+2	3	Combined advanced rounds
Div.1	3	Top-tier rounds
Special	13	Global Round, CodeTON, Pinely, EPIC, Hello/Goodbye, etc.

🟢 AtCoder — 109 Problems / 21 Contests

Covering ABC 331 – 433 and ARC 170, etc.

🟠 Nowcoder — 756 Problems

Series	Content
Weekly Contest	Round 1 – 91 (69 contests)
Summer Training Camp 2024	Camp 1 – 10
Winter Training Camp 2024	Camp 1 – 6
May Day Training Camp 2024	May Day Special
Code Faster 2025	Speed practice
noob / Practice / Challenge / Entertainment	Multi-mode practice
Provincial / League Contests	2024 & 2025 Henan Freshman Contest

🔵 Virtual Participation — 806 Problems / 133 Contests

VP records spanning 2024 – 2026, covering historical ICPC / CCPC regionals, provincials, and invitationals.

Year	VP Contests	Highlighted Events
2024	79	CCPC Final, ICPC Regionals (Shenyang/Nanjing/Hangzhou/Chengdu), Provincial contests
2025	47	ICPC Xi'an/Nanjing, CCPC Harbin/Chongqing, Multi-provincial & Invitational
2026	7	ICPC Hong Kong/Shenyang, GPLT, etc.

🟡 Other Platforms

Platform	Problems	Description
PTA	559	PAT (Basic Level), GPLT (Group Programming Ladder Tournament), RuiKang
HDU	247	Dingba Programming Super League 2024/2025, etc.
LanQiao Cloud	187	LanQiao Cup CA/CB Provincial & National (2023–2025), Algorithm contests
Matiji	170	Matiji Cup, Baidu Star, Elite Class
Luogu	208	Topic-classified: Intro → Basics → Search → DP → Strings → Math → Data Structures → Graphs → Computational Geometry

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📐 Algorithm Template Library (45 Templates)

Path: 12 XCPC模板/, with a complete PDF reference at XCPC.pdf.

Graph Theory (15)

Template	Template	Template
Dijkstra	Floyd	SPFA (Negative Cycle Detection)
LCA	Topological Sort	Minimum Spanning Tree
Tree Diameter	Heavy-Light Decomposition	Tarjan SCC
Bipartite Graph	Cut Vertices	Difference Constraints
Max Flow	2-SAT	DSU on Tree

Strings (8)

Template	Template	Template
KMP	Z-function	Manacher
Aho-Corasick	Trie	Persistent Trie
Suffix Automaton (SAM)	String Hashing

Mathematics (13)

Template	Template	Template
GCD & LCM	Linear Sieve	Euler's Totient Function
Fermat's Little Theorem	Modular Inverse	Lucas' Theorem
Combinations	Matrix Exponentiation	Linear Basis
Ternary Search	Sprague-Grundy	Stirling Numbers
Bézout's Identity

Data Structures (9)

Template	Template	Template
Segment Tree	Dynamic Segment Tree	Segment Tree + Bitset
Persistent Segment Tree	Binary Indexed Tree	Sparse Table
Disjoint Set Union	Binary Heap	Mo's Algorithm

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📖 Luogu Topic Classification

Luogu problems are organized into 13 topics, inspired by "Advanced Guide to Algorithm Competitions":

#	Topic	#	Topic
1	Introduction	8	Graph Theory (13 subtopics)
2	Fundamental Algorithms	9	Computational Geometry
3	Search	10	Miscellaneous
4	Dynamic Programming (12 types)	—	—
5	Strings	—	—
6	Mathematics	—	—
7	Data Structures	—	—

📋 DP Subtopics (12 types)

1. Linear DP
2. Knapsack DP
3. Interval DP
4. Tree DP
5. Bitmask DP
6. Binary Lifting DP
7. Data Structure Optimized DP
8. Monotone Queue Optimized DP
9. Convex Hull Trick DP
10. Decision Monotonicity DP
11. Digit DP
12. Profile DP (Broken Profile)

📋 Graph Theory Subtopics (13 types)

1. Graph Representation & Traversal
2. Shortest Paths
3. Tree Problems
4. Spanning Trees
5. Topological Sort
6. Difference Constraints
7. Graph Connectivity
8. Bipartite Graphs
9. Network Flow
10. 2-SAT
11. Centroid Decomposition
12. Virtual Tree
13. Matrix-Tree Theorem

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📏 Naming & Organization Conventions

• Top-level directories: Numbered by platform/source (00 – 12)
• Codeforces: {RoundID} {DivLevel} {Date} — e.g., 1000 div2 01.22
• AtCoder: {Date} {ContestID} — e.g., 24.01.20 ABC337
• VP: {Date} {Year} {Full Contest Name} — e.g., 11.24 2024 ICPC Shenyang Regional
• Per-contest files: A.cpp, B.cpp, C.cpp… named by problem label

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🛠️ Build & Run Locally

Requires g++ (C++17 or later recommended).

Windows (PowerShell)

cd "E:\XCPC\00 Codeforces\1000 div2 01.22"
g++ -std=c++17 -O2 -pipe A.cpp -o A.exe
.\A.exe

Linux / WSL

cd "00 Codeforces/1000 div2 01.22"
g++ -std=c++17 -O2 -pipe A.cpp -o A
./A

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📜 License

This repository is primarily for personal competitive programming training and progress tracking. Continuously updated.

If you find this repo helpful, feel free to ⭐ star it!