LeetCode 712 | Minimum ASCII Delete Sum for Two Strings | Java | Medium | 2D D P | CodeByTushu
Description: 🚀 Welcome Back to CodeByTushu!
In today’s video, we solve LeetCode 712 — Minimum ASCII Delete Sum for Two Strings using String and Dynamic Programming in Java.
Given two strings s1 and s2, our objective is to find the lowest total ASCII value of deleted characters necessary to make both strings completely identical. This problem represents an ASCII-weighted variation of the classic Longest Common Subsequence (LCS) and Edit Distance paradigms. Rather than counting the number of deletions, we accumulate the numerical ASCII weight of every character removed, optimizing to preserve the subsequence with maximum aggregate ASCII value.
We formulate a 2D dynamic programming grid where dp[i][j] denotes the minimum ASCII deletion cost required to equalize prefix s1[0..i-1] with prefix s2[0..j-1]. When characters match at s1[i-1] and s2[j-1], no deletion is required, allowing us to carry forward the previous diagonal subproblem cost. When characters differ, we choose the minimum between deleting s1[i-1] or deleting s2[j-1]. This structured table computation achieves an optimal O(M * N) time and auxiliary space complexity.
🔥 Problem Highlights
✅ 2D Dynamic Programming table formulation for character prefix alignment
✅ Weighted variation of Longest Common Subsequence (LCS) based on ASCII values
✅ Optimal subproblem recurrence with base cases handling empty string prefixes
✅ Robust handling of strings of unequal length and completely disjoint characters
✅ Idiomatic clean solutions across Java, Python, C++, and JavaScript
✅ Optimal O(M * N) time complexity and O(M * N) auxiliary space complexity
⏱️ TIMESTAMPS
00:00 Intro
00:52 Problem Understanding
01:52 Observation & Mathematical Intuition
02:39 2D Dynamic Programming Approach
03:42 Java Code Walkthrough
04:49 Test Cases & Edge Cases Walkthrough
05:38 Time Complexity Analysis
06:11 Space Complexity Analysis
06:40 Summary & Outro
📂 Problem Folder & Detailed Documentation:
https://github.com/CodeByTushu/CodeByTushu-LeetCode-Solutions/tree/main/solutions/January/10-January/712-Minimum-ASCII-Delete-Sum-for-Two-Strings
☕ Java Solution:
https://github.com/CodeByTushu/CodeByTushu-LeetCode-Solutions/blob/main/solutions/January/10-January/712-Minimum-ASCII-Delete-Sum-for-Two-Strings/Solution.java
🐍 Python Solution:
https://github.com/CodeByTushu/CodeByTushu-LeetCode-Solutions/blob/main/solutions/January/10-January/712-Minimum-ASCII-Delete-Sum-for-Two-Strings/solution.py
⚡ C++ Solution:
https://github.com/CodeByTushu/CodeByTushu-LeetCode-Solutions/blob/main/solutions/January/10-January/712-Minimum-ASCII-Delete-Sum-for-Two-Strings/solution.cpp
🌐 JavaScript Solution:
https://github.com/CodeByTushu/CodeByTushu-LeetCode-Solutions/blob/main/solutions/January/10-January/712-Minimum-ASCII-Delete-Sum-for-Two-Strings/solution.js
🔗 LeetCode Source Code
📌 Admin type the link
🌐 All LeetCode Solutions
📌 https://codebytushu.com/Leetcode/
📱 Join CodeByTushu on WhatsApp
Get coding updates, LeetCode solutions, daily questions and more.
https://whatsapp.com/channel/0029Vb8k5mCDeON2Xwlkxe40
❤️ Donate
📌 https://codebytushu.com/Leetcode/donate.php
🔥 Perfect For
LeetCode Medium Problems
Java DSA Preparation
Dynamic Programming (DP)
String Algorithms
Edit Distance Patterns
Time Complexity Optimization
Coding Interview Preparation
Problem Solving
🌐 Follow CodeByTushu
▶️ YouTube: https://www.youtube.com/@codebytushu
📸 Instagram: https://instagram.com/codebytushu/
💼 LinkedIn: https://www.linkedin.com/company/codebytushu/
🌍 Website: https://codebytushu.com
🐙 GitHub: https://github.com/CodeByTushu
❤️ Don’t Forget To
👍 Like | 💬 Comment | 🔔 Subscribe
💬 Question of the Day
In the DP transition for LeetCode 712, if characters s1[i-1] and s2[j-1] match, what is the exact transition rule?
1️⃣ dp[i][j] = dp[i-1][j-1] + ASCII(s1[i-1])
2️⃣ dp[i][j] = dp[i-1][j-1]
3️⃣ dp[i][j] = min(dp[i-1][j], dp[i][j-1])
4️⃣ dp[i][j] = dp[i-1][j-1] + ASCII(s1[i-1]) + ASCII(s2[j-1])
#LeetCode712 #LeetCode #MinimumASCIIDeleteSumForTwoStrings #Java #JavaDSA #DynamicProgramming #StringAlgorithms #DSA #CodingInterview #ProblemSolving #LeetCodeMedium #DailyLeetCode #JavaProgramming #CodeByTushu
👇 Comment the answer below! 🔥 Close description
In today’s video, we solve LeetCode 712 — Minimum ASCII Delete Sum for Two Strings using String and Dynamic Programming in Java.
Given two strings s1 and s2, our objective is to find the lowest total ASCII value of deleted characters necessary to make both strings completely identical. This problem represents an ASCII-weighted variation of the classic Longest Common Subsequence (LCS) and Edit Distance paradigms. Rather than counting the number of deletions, we accumulate the numerical ASCII weight of every character removed, optimizing to preserve the subsequence with maximum aggregate ASCII value.
We formulate a 2D dynamic programming grid where dp[i][j] denotes the minimum ASCII deletion cost required to equalize prefix s1[0..i-1] with prefix s2[0..j-1]. When characters match at s1[i-1] and s2[j-1], no deletion is required, allowing us to carry forward the previous diagonal subproblem cost. When characters differ, we choose the minimum between deleting s1[i-1] or deleting s2[j-1]. This structured table computation achieves an optimal O(M * N) time and auxiliary space complexity.
🔥 Problem Highlights
✅ 2D Dynamic Programming table formulation for character prefix alignment
✅ Weighted variation of Longest Common Subsequence (LCS) based on ASCII values
✅ Optimal subproblem recurrence with base cases handling empty string prefixes
✅ Robust handling of strings of unequal length and completely disjoint characters
✅ Idiomatic clean solutions across Java, Python, C++, and JavaScript
✅ Optimal O(M * N) time complexity and O(M * N) auxiliary space complexity
⏱️ TIMESTAMPS
00:00 Intro
00:52 Problem Understanding
01:52 Observation & Mathematical Intuition
02:39 2D Dynamic Programming Approach
03:42 Java Code Walkthrough
04:49 Test Cases & Edge Cases Walkthrough
05:38 Time Complexity Analysis
06:11 Space Complexity Analysis
06:40 Summary & Outro
📂 Problem Folder & Detailed Documentation:
https://github.com/CodeByTushu/CodeByTushu-LeetCode-Solutions/tree/main/solutions/January/10-January/712-Minimum-ASCII-Delete-Sum-for-Two-Strings
☕ Java Solution:
https://github.com/CodeByTushu/CodeByTushu-LeetCode-Solutions/blob/main/solutions/January/10-January/712-Minimum-ASCII-Delete-Sum-for-Two-Strings/Solution.java
🐍 Python Solution:
https://github.com/CodeByTushu/CodeByTushu-LeetCode-Solutions/blob/main/solutions/January/10-January/712-Minimum-ASCII-Delete-Sum-for-Two-Strings/solution.py
⚡ C++ Solution:
https://github.com/CodeByTushu/CodeByTushu-LeetCode-Solutions/blob/main/solutions/January/10-January/712-Minimum-ASCII-Delete-Sum-for-Two-Strings/solution.cpp
🌐 JavaScript Solution:
https://github.com/CodeByTushu/CodeByTushu-LeetCode-Solutions/blob/main/solutions/January/10-January/712-Minimum-ASCII-Delete-Sum-for-Two-Strings/solution.js
🔗 LeetCode Source Code
📌 Admin type the link
🌐 All LeetCode Solutions
📌 https://codebytushu.com/Leetcode/
📱 Join CodeByTushu on WhatsApp
Get coding updates, LeetCode solutions, daily questions and more.
https://whatsapp.com/channel/0029Vb8k5mCDeON2Xwlkxe40
❤️ Donate
📌 https://codebytushu.com/Leetcode/donate.php
🔥 Perfect For
LeetCode Medium Problems
Java DSA Preparation
Dynamic Programming (DP)
String Algorithms
Edit Distance Patterns
Time Complexity Optimization
Coding Interview Preparation
Problem Solving
🌐 Follow CodeByTushu
▶️ YouTube: https://www.youtube.com/@codebytushu
📸 Instagram: https://instagram.com/codebytushu/
💼 LinkedIn: https://www.linkedin.com/company/codebytushu/
🌍 Website: https://codebytushu.com
🐙 GitHub: https://github.com/CodeByTushu
❤️ Don’t Forget To
👍 Like | 💬 Comment | 🔔 Subscribe
💬 Question of the Day
In the DP transition for LeetCode 712, if characters s1[i-1] and s2[j-1] match, what is the exact transition rule?
1️⃣ dp[i][j] = dp[i-1][j-1] + ASCII(s1[i-1])
2️⃣ dp[i][j] = dp[i-1][j-1]
3️⃣ dp[i][j] = min(dp[i-1][j], dp[i][j-1])
4️⃣ dp[i][j] = dp[i-1][j-1] + ASCII(s1[i-1]) + ASCII(s2[j-1])
#LeetCode712 #LeetCode #MinimumASCIIDeleteSumForTwoStrings #Java #JavaDSA #DynamicProgramming #StringAlgorithms #DSA #CodingInterview #ProblemSolving #LeetCodeMedium #DailyLeetCode #JavaProgramming #CodeByTushu
👇 Comment the answer below! 🔥 Close description
