dynamic programming Pattern
11 problems
Pattern pages help build reusable solving frames. Identify signals first, then explain state, transition, and edge handling.
Recognition Signals
- The candidate should understand how to efficiently traverse the matrix using graph-like techniques such as topological sort.
- Look for a clear explanation of how DFS with memoization avoids recalculating paths.
- The candidate demonstrates proficiency in dynamic programming and graph traversal.
Solve Flow
- 1. Define the active state/window.
- 2. Update state while preserving invariants.
- 3. Validate with edge-heavy examples.
Common Misses
- Ignoring boundary conditions and invalid moves (e.g., out-of-bound or non-increasing paths).
- Not considering bitmasking as an efficient way to track visited nodes.
- Failing to account for the Cat cannot move to node 0, breaking correct state transitions.
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