math plus sorting Pattern

Recognition Signals

• Can the candidate handle edge cases like leading zeros and negative numbers effectively?
• Does the candidate demonstrate an understanding of sorting algorithms?
• Check if candidate handles repeated digits correctly.

Solve Flow

1. 1. Define the active state/window.
2. 2. Update state while preserving invariants.
3. 3. Validate with edge-heavy examples.

Common Misses

• Forgetting to handle leading zeros for positive numbers.
• Forgetting that digits can repeat and pair with themselves.