math recursion Pattern
7 problems
Pattern pages help build reusable solving frames. Identify signals first, then explain state, transition, and edge handling.
Recognition Signals
- Recognizes negative exponent handling is required.
- Uses recursion to optimize repeated multiplications.
- Look for understanding of recursion and factorials.
Solve Flow
- 1. Define the active state/window.
- 2. Update state while preserving invariants.
- 3. Validate with edge-heavy examples.
Common Misses
- Failing to handle n = INT_MIN correctly when negating.
- Misunderstanding how factorials divide the problem into smaller sections, leading to incorrect permutation generation.
- Not handling negative numbers or zero correctly, which can lead to incorrect answers.
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