CustomCC0-1.0#p0041600
Lexicographically Minimal Path Grid
Summary
- •Phase 1 / dp, lex_order
- •Reasoning-first competitive programming drill
Problem Description
Given an n×n grid of lowercase letters, find a path from (1,1) to (n,n) moving only right or down, such that the concatenated string is lexicographically minimal.
How to read this problem in plain language:
- This is a Phase 1 reasoning drill focused on dp, le.
- Typical lenses to test first: dp, grid, strings.
- Constraints reminder: 1 ≤
Mini examples for mental simulation:
1) Boundary example: Describe why this case is tricky. Explain expected behavior and why naive logic may fail.
2) Adversarial example: Adversarial case where naive greedy/local decision looks correct but fails globally.
Lite-mode writing target:
- Write 1~2 observations that shrink the search space.
- Name one final algorithm and state target complexity explicitly.
- Validate with at least 2 edge cases and one hand simulation.
Constraints
- •1 ≤
Analysis
Key Insight
Use this hint to refine your reasoning. This step should reduce search space or formalize correctness. State why this insight changes your algorithm choice.
dpgridstringslexicographical