Odin's Warrior Cascade - Competitive Programming Problem

This directory contains a complete competitive programming problem setup with automated testing infrastructure.

📁 Project Structure

• qwen/: Contains failed solution attempts by Qwen model (educational purposes)
• test_cases/: Input/output test cases (comprehensive test suite)
• idea.md: Problem development process and insights
• problem.md: Complete problem statement with examples
• solution.md: Detailed solution explanation with chain reaction analysis
• solution.cpp: Optimal O(n log n) accepted solution
• requirements.json: Time (4s) and memory (512MB) constraints
• solution_bf.cpp: Brute-force solution for comparison
• generator.cpp: Test case generator framework

🚀 Quick Start

1. Read the problem statement in problem.md
2. Try to solve it yourself
3. Check your approach against solution.md
4. Test your solution using the automated test runners

🔧 Building and Testing

Automated Test Runners

This project includes multiple test runner scripts with comprehensive features:

PowerShell Script (Windows) - Recommended

# Test the optimal solution
.\test_runner.ps1 solution.cpp

# Test specific solutions
.\test_runner.ps1 qwen\solution_01.cpp
.\test_runner.ps1 solution_bf.cpp

# Custom test directory
.\test_runner.ps1 solution.cpp test_cases

Batch Script (Windows Command Prompt)

test_runner.bat solution.cpp
test_runner.bat qwen\solution_01.cpp

Bash Script (Linux/macOS)

chmod +x test_runner.sh
./test_runner.sh solution.cpp
./test_runner.sh qwen/solution_01.cpp

Manual Compilation

# Using VS Code task (Build C++ file)
Ctrl+Shift+P -> "Tasks: Run Task" -> "Build C++ file"

# Manual compilation
g++ -Wall -Wextra -g3 solution.cpp -o solution.exe

# Run against specific test case
.\solution.exe < test_cases\1.in

🧪 Test Runner Features

Comprehensive Testing

• Automatic compilation with error handling
• Time limit enforcement (4 seconds per test case)
• Memory limit monitoring (512MB)
• Detailed output comparison with diff visualization
• Colored output (Pass/Fail/TLE/MLE)
• Performance metrics (execution time per test)
• Multiple answer validation (supports brute-force generated answers)

Example Output

=== C++ Solution Test Runner ===
Solution: solution.cpp
Test Cases Directory: test_cases
Requirements: 4000ms timeout, 512MB memory limit

Compiling solution.cpp...
Compilation successful!

Running 8 test cases...

Test 1... PASS (15ms)
Test 2... PASS (12ms)
Test 3... PASS (847ms)
Test 4... TLE (>4000ms)
Test 5... PASS (1205ms)

=== Test Results ===
Passed: 4/5 tests
Failed Tests:
  - Test 4: Time Limit Exceeded (TLE)

Some tests failed! ✗

📊 Solution Variants

1. Optimal Solution (solution.cpp)

• Algorithm: Greedy with DFS timing and interval-based chain simulation
• Time Complexity: O(n log n)
• Space Complexity: O(n)
• Status: Passes all test cases

2. Brute Force (solution_bf.cpp)

• Algorithm: Recursive game tree exploration
• Time Complexity: O(n³)
• Purpose: Generate all valid answers, verify correctness

3. Qwen Attempts (qwen/)

• solution_01.cpp: Sophisticated but flawed (TLE on large cases)
• solution_02.cpp: Multiple failure modes (WA, TLE, RE)
• solution_03.cpp: Additional failed approach
• Purpose: Educational - demonstrates common competitive programming mistakes

🔍 Test Case Structure

test_cases/
├── 1.in     # Sample input from problem statement
├── 1.out    # Expected output
├── 2.in     # Edge case: single node
├── 2.out    # Expected: 0 (no valid moves)
├── 3.in     # Small tree with multiple valid answers
├── 3.out    # One of the valid answers
├── 4.in     # Medium complexity
├── 4.out    # Expected output
├── 5.in     # Large case (stress test)
├── 5.out    # Expected output
└── ...

🐛 Troubleshooting

Compilation Issues

• Ensure MinGW/GCC is installed and in PATH
• Check C++ syntax and missing headers
• Verify compiler version supports C++17 features

Runtime Issues

• Time Limit Exceeded: Optimize algorithm complexity
• Memory Limit Exceeded: Reduce memory usage
• Wrong Answer: Check edge cases and logic
• Runtime Error: Handle array bounds and null pointers

Path Issues

• Use absolute paths if relative paths fail
• Ensure test_cases/ directory exists
• Check file permissions on Unix systems

📈 Performance Analysis

Solution	Time Complexity	Space	Test Results
Optimal	O(n log n)	O(n)	8/8 PASS
Brute Force	O(n³)	O(n)	6/8 PASS (TLE on large)
Qwen-01	O(n² log n)	O(n)	7/8 PASS (TLE on largest)
Qwen-02	O(n³)	O(n²)	3/8 PASS (Multiple issues)

🎯 Testing All Solutions

# Quick test all variants
.\test_runner.ps1 solution.cpp         # Should pass all
.\test_runner.ps1 solution_bf.cpp      # Should pass most (TLE on large)
.\test_runner.ps1 qwen\solution_01.cpp # Should show realistic TLE
.\test_runner.ps1 qwen\solution_02.cpp # Should show multiple failure modes
.\test_runner.ps1 qwen\solution_03.cpp # Additional failed approach

📚 Educational Value

• Algorithm Design: Learn advanced techniques (DFS timing, interval arithmetic, game theory)
• Optimization: Understand the progression from O(n³) to O(n log n)
• Debugging: Analyze failed solutions to understand common pitfalls
• Testing: Experience comprehensive test-driven development
• Chain Reaction Modeling: Complex state transitions and mathematical modeling

🏆 Competition Tips

1. Read carefully: Understand the chain reaction mechanism
2. Start simple: Implement brute force first for small cases
3. Optimize incrementally: Identify bottlenecks and improve
4. Test thoroughly: Use provided test runners for validation
5. Handle edge cases: Single nodes, equal strengths, cycles

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Note: The Qwen model attempts are intentionally flawed for educational purposes, demonstrating realistic competitive programming mistakes and optimization challenges.