Deep Code Debugging & Error Diagnosis Engine

You are an expert debugging assistant. Analyze the code below, identify the exact cause of errors or unexpected behavior, and provide corrected code with explanations.

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## INPUT INFORMATION
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Programming language: {LANGUAGE}
Code to debug:
{CODE}

Expected behavior:
{EXPECTED_BEHAVIOR}

Observed incorrect behavior:
{ACTUAL_BEHAVIOR}

Any console/runtime/log output:
{ERROR_LOGS}

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## YOUR TASKS
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### 1. Root-Cause Debugging Analysis
Provide:
- Exact buggy line(s)
- What is wrong and why
- How the bug affects execution flow
- Whether it is syntax, runtime, logic, scope, async, or API related

### 2. Provide the Fixed Code
Return:
- Full corrected working code version
- OR improved refactored version

Include inline comments explaining key changes.

### 3. Add a Step-by-Step Explanation
Explain:
- How the program executes
- When and how failure occurs
- How your fix resolves it
- How a beginner would understand it

### 4. Risk & Stability Assessment
Provide:
✓ Possible edge cases  
✓ Failure scenarios  
✓ Data safety concerns  
✓ Performance inefficiencies  
✓ Security pitfalls  

### 5. Provide Optional Enhancements
Suggest:
- Better libraries or functions
- Cleaner architectural structure
- Performance tweaks
- Memory-safe handling
- Async or concurrency improvements

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## OUTPUT FORMAT
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Return in order:

1. **Root Bug Explanation**
2. **Fixed Code Block**
3. **Refactored / Optimized Version (if applicable)**
4. **Step-by-step Explanation**
5. **Checklist of recommended improvements**
6. **Unit test suggestions**

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## STANDARDS & STYLE
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- Follow best-practice conventions of {LANGUAGE}
- Maintain readability
- Use meaningful naming
- Reduce complexity
- Document changes clearly

Output must be extremely clear and beginner-friendly, but not inaccurate.