LeetCode Daily Challenge - Minimum ASCII Delete Sum for Two Strings

🚀 LeetCode Daily Challenge – Day 10 Problem #712: Minimum ASCII Delete Sum for Two Strings (Medium) This was a really interesting Dynamic Programming + Strings problem that made me think beyond the usual edit-distance pattern. 🧭 How I Approached the Question: Instead of directly minimizing the delete cost, I flipped the perspective. 👉 If I can maximize the ASCII sum of the common subsequence between the two strings, then: The characters not in this subsequence are the ones that must be deleted The minimum delete cost = (total ASCII of s1 + total ASCII of s2) − 2 × (ASCII sum of common subsequence) So the problem becomes: ➡️ Find the maximum ASCII sum common subsequence (a weighted LCS). 🧠 Core Insight: I used a 2D DP table where: dp[i][j] represents the maximum ASCII sum of a common subsequence between s1[:i] and s2[:j] Transition: If characters match → add their ASCII value Else → carry forward the best result by skipping one character 🛠️ Why This Works: By maximizing what we keep, we automatically minimize what we delete. This reframing made the solution much cleaner and intuitive. ⏱ Time Complexity: O(n × m) 📦 Space Complexity: O(n × m) #LeetCode #DailyCoding #DynamicProgramming #Strings #ProblemSolving #DSA #Python #CodingJourney

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