competitive-programming-expert

# Competitive Programming Problem Solver ## Description Solve competitive programming problems with optimal solutions, complexity analysis, and complete code implementation. ## When to Use - User provides problem link or description from LeetCode/Codeforces/AtCoder/ACM-ICPC platforms - User requests "solve this algorithm problem" or "optimize this solution" - User asks for specific algorithm/data structure implementation (e.g., "how to implement segment tree") - User's code encounters TLE/MLE/WA and needs debugging - User asks for solution templates or patterns for certain problem types ## When NOT to Use - User only asks about algorithm concepts or theory without specific problem - User needs algorithm design for software engineering, not competitive programming - User is doing system design or architecture problems - User only needs code completion or syntax help without algorithmic logic ## Input ```typescript { problem: string // Problem description or link platform?: string // Platform name (leetcode/codeforces/atcoder, etc.) language?: string // Preferred language (default: C++ or Python) userCode?: string // User's existing code (for optimization/debugging) constraints?: { // Problem constraints timeLimit?: string // e.g., "1s", "2s" memoryLimit?: string // e.g., "256MB" inputSize?: string // e.g., "n ≤ 10^5" } } ``` ## Output ```typescript { analysis: { type: string // Problem type (DP/Graph/Greedy/Number Theory, etc.) keyInsight: string // Core idea edgeCases: string[] // Edge cases to consider } solution: { approach: string // Solution explanation complexity: { time: string // Time complexity (e.g., O(n log n)) space: string // Space complexity justification: string // Why it meets problem constraints } code: string // Complete executable code } optimization?: string // Optional optimization suggestions } ``` ## Execution Steps ### Step 1: Understand Constraints - Extract input size upper bound (e.g., n ≤ 10^5) - Calculate time budget (typically 1s ≈ 10^8 operations) - Identify special restrictions (e.g., read-only once, online algorithm) ### Step 2: Classify and Model - Categorize problem into known algorithm types (DP/Graph/Greedy/Number Theory/String/Computational Geometry) - Extract mathematical model or state definition - List at least 3 typical edge cases ### Step 3: Design Solution - Explain core idea in 1-2 sentences - For non-obvious algorithms (e.g., greedy/constructive), briefly justify correctness - Specify time and space complexity ### Step 4: Implement Code Output code according to platform conventions: - **LeetCode**: Provide class/function definition without main function - **Codeforces/AtCoder**: Provide complete code with standard I/O - **Other platforms**: Ask user preference Code requirements: - Clear variable naming - Comments on key steps - Cover identified edge cases ### Step 5: Verify and Optimize - Validate correctness with sample inputs - If user provides existing code, compare differences and identify bottlenecks - If constant-factor optimizations exist (e.g., fast I/O, bitwise tricks), mention separately ## Failure Handling - **Unclear problem**: Request complete problem statement or link - **Missing constraints**: Ask for input size bounds and time limits - **No optimal solution exists**: Provide passable solution first, then discuss if better approach exists - **Language not supported**: Explain language limitations and suggest alternatives ## See Also - `cpp-expert` — language-level optimization, STL, and UB concerns for C++ submissions. - `python-expert` — fast I/O and idiomatic patterns for Python submissions. - `software-architect` — when the problem is system design rather than a contest task.