Optimizing LeetCode Problem 3661 with Dynamic Programming

Day 93: Optimization > Completion 📉 Problem 3661: Maximum Walls Destroyed by Robots Today was a massive lesson in efficiency. I initially cleared all test cases with a Memoization + Binary Search approach, but at O(N²), I knew it wasn't the most optimal way to handle the constraints. I decided to dig deeper and refactor the entire logic into a cleaner Dynamic Programming solution. The Strategy Shift: • The O(N²) Trap: My first pass worked, but nested recursion with memoization can get heavy. I wanted to see if I could solve it in a single linear pass. • State Transition: I moved to a DP approach using subLeft and subRight to track the maximum walls destroyed up to each robot. • Precision Boundary Logic: By pre-calculating the left and right firing ranges for each robot using Binary Search (lowerBound/upperBound), I could transition states in O(N) time. I’m honestly not proud of my initial approach today. It felt a bit like forcing a solution rather than finding the most elegant one. Pushing myself to find the O(N) path when I already had a working "Pass" was the real challenge, but it’s where the growth happens. We go again tomorrow. 🚀 #LeetCode #Java #DynamicProgramming #BinarySearch #Algorithms #DailyCode

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