Algorithm Practice

A collection of 81 algorithm problems with Python solutions, originally from the ByteDance MarsCode Youth Training Camp. Each problem includes a detailed description, solution approach, complexity analysis, and tested implementation.

Getting Started

git clone https://github.com/ChanMeng666/juejin-algorithm-practice.git
cd juejin-algorithm-practice

# Run any solution
python problems/001-find-unique-number/solution.py

# Read the problem description
cat problems/001-find-unique-number/README.md

Structure

problems/
  001-find-unique-number/
    README.md       # Problem description, examples, and solution explanation
    solution.py     # Python solution with test cases
  002-optimal-food-supply-strategy/
    ...

Topics Covered

Topic	Examples
Arrays & Strings	Majority element, string transformation, pattern matching
Dynamic Programming	Edit distance, stock trading, subarray optimization
Greedy Algorithms	Optimal refueling, food supply, menu selection
Math & Number Theory	Combination sum, percentile calculation, probability
Binary Search	Monster sequence, arena escape
Graph & Tree	Flight routes, virus propagation, tree traversal
Bit Manipulation	Find unique number, XOR operations
Sorting & Searching	Top-K elements, multi-criteria sorting
Simulation	Board games, card games, shooting scores
Encoding & Decoding	Base32, binary strings, RGB conversion

Problem Index

#	Problem	Topics
001	Find Unique Number	Bit Manipulation, Arrays
002	Optimal Food Supply Strategy	Greedy, Arrays
003	Number Thousands Separator	Strings, Formatting
004	Combination Sum	Backtracking, Recursion
005	Texas Hold'em Full House	Sorting, Simulation
006	Longest Defeatable Monster Sequence	Greedy, Sorting
007	Wildcard Matching	DP, Strings
008	Majority Element	Arrays, Voting Algorithm
009	Supermarket Product Arrangement	Greedy, Sorting
010	Token Card Breakeven	Math, Simulation
011	Best Sightseeing Pair	DP, Arrays
012	Max UCC Substring Count	Strings, Counting
013	Construct Pattern Array	Arrays, Construction
014	Construct Minimum Sum Array	Greedy, Arrays
015	String Prefix Transformation	Strings, Simulation
016	Largest Rectangle Area	Stack, Arrays
017	Array Transformation	Arrays, Math
018	Alternating Uphill Downhill Path	DP, Arrays
019	Lexicographically Smallest String	Greedy, Strings
020	Tournament Pairing	Simulation, Math
021	Circular Array Max Contribution	Arrays, Prefix Sum
022	Minimum String Operations	Strings, Greedy
023	Stone Jumping Game	DP, Game Theory
024	Special Playlist Order	Arrays, Simulation
025	DNA Sequence Edit Distance	DP, Strings
026	Digit Insertion	Greedy, Strings
027	Hero Training	DP, Greedy
028	Arena Escape	Binary Search, Greedy
029	String Conversion	Strings, Counting
030	Max "ku" Count in String	Strings, Greedy
031	Count Distinct Integers in String	Strings, Parsing
032	Digit Sum Game	Math, Game Theory
033	Card Flip Sum	Greedy, Arrays
034	Third Largest Number	Arrays, Sorting
035	Inverted Index Intersection	Arrays, Two Pointers
036	Optimal Menu Selection	DP, Knapsack
037	Smallest Non-Palindrome	Strings, Greedy
038	Travel Optimal Resupply	Greedy, Simulation
039	AB Experiment Minimum Steps	BFS, Strings
040	Circular DNA Minimum Representation	Strings, Comparison
041	Balanced ASDF String	Strings, Sliding Window
042	Tree Gift Decoration	Trees, DFS
043	Restore Original String	Strings, Deque
044	Shooting Score Calculator	Simulation, Arrays
045	Digit Removal	Greedy, Stack
046	Large Number Addition	Math, Strings
047	Perfect Even Count	Math, Counting
048	String Replacement	Strings, Simulation
049	Multi-Criteria Sorting	Sorting, Custom Comparator
050	Optimal Refueling Strategy	Greedy, Simulation
051	Reconstruct Array from Pair Sums	Math, Construction
052	Basic Calculator	Stack, Parsing
053	Course Score Combinations	DP, Backtracking
054	Decode Numbers to String	DP, Strings
055	Binary String Sum to Decimal	Math, Binary
056	Cat Fish Distribution	Greedy, Math
057	Red Packet Three-Way Split	Math, Combinatorics
058	Base32 Encode/Decode	Encoding, Bit Manipulation
059	Binary String Flip Optimization	DP, Strings
060	RGB to Hex Integer	Math, Bit Manipulation
061	Optimal Flight Route	Graph, DP
062	Virus Propagation	Graph, BFS
063	Percentile Calculation	Math, Statistics
064	Hero Battle Sequence	Greedy, Sorting
065	Needle Rain Shooting	Geometry, Simulation
066	Dessert Preference Matching	Sorting, Two Pointers
067	Number Guessing Probability	Math, Probability
068	Journey Water Supply	Greedy, Simulation
069	Top K Frequent Elements	Hash Map, Sorting
070	Dot Counter	Arrays, Interval
071	Cake Factory Optimization	DP, Optimization
072	Domino Tiling	DP, Math
073	SQL Editor Autocomplete	Trie, Strings
074	Plate Stacking	Greedy, Stack
075	Binary Tree Node Count	Trees, Recursion
076	Group Familiarity Optimization	Graph, DP
077	Quality Chapter Selection	DP, Arrays
078	Board Game Piece Grouping	Math, Counting
079	Max Subarray Sum with Flip	DP, Arrays
080	Stock Trading with Cooldown	DP, State Machine
081	DNA Edit Distance	DP, Strings

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

1. Fork the repository
2. Create your feature branch (git checkout -b feature/improvement)
3. Commit your changes (git commit -m 'Add improvement')
4. Push to the branch (git push origin feature/improvement)
5. Open a Pull Request

License

This project is licensed under the MIT License - see the LICENSE file for details.

Author

Chan Meng - GitHub