Linked List Addition: Traverse and Add Digits

🚀 Day 81 of #100DaysOfCode 💡 Question 22: Generate Parentheses 🔍 Problem Statement: Given n pairs of parentheses, generate all combinations of well-formed parentheses. 🧠 Approach: - Use recursion with backtracking - Add an opening bracket if limit not reached - Add a closing bracket only if it keeps the sequence valid - Ensure balance at every step 📌 Key Takeaways: - Classic backtracking problem - Focus on constraints rather than brute force - Helps build strong recursion understanding 🔥 Solved successfully with optimized approach! #Day81 #100DaysOfCode #LeetCode #DSA #Backtracking #Coding #ProgrammingJourney

Understanding Lowest Common Ancestor (LCA) made simple. From recursion basics to real-world use cases like file systems and Git merges. 👉 Whenever you see a hierarchy and need a common parent — think LCA. #DSA #Algorithms #Coding #SystemDesign #Recursion

💡 Day 213 ✅ Longest Subarray with Sum = K (Quick Insight) Use Prefix Sum + HashMap to solve in O(n) ⚡ Key Points Store first occurrence of prefix sum Works with negative numbers Sliding window ❌ (not reliable here) #DSA #Coding #LeetCode #LongestSubarraywithSumequaltoK

Today’s win: Two Sum Brute force worked… but understanding optimization is the real game Learning to think better, not just code better. #Coding #DSA #DeveloperJourney #LeetCode

Solved the classic Two Sum problem using an optimized approach. Instead of checking every pair (O(n²)), used a hash map to reduce it to O(n) time. Idea: For each element, calculate the required complement and check if it already exists. If yes, return the indices immediately. #DSA #Coding #CPP #ProblemSolving

Day-28 Solved the Count and Say problem today and it turned out to be a really good exercise in string manipulation. 👉 The idea is simple: start with "1" and keep generating the next term by describing the previous one. 👉 You only count consecutive digits, not overall frequency. 👉 Example: "1" → "11" → "21" → "1211" 💡 What I learned: Always think in terms of patterns Handle edge cases carefully (especially index bounds ⚠️) Small bugs like accessing i+1 without checking can break everything 🛠️ Concepts used: Strings Loops to_string() It looked confusing at first, but once the pattern clicked, it became straightforward. #leetcode #cpp #dsa #coding #learning

Day-38 Remove Outer Parentheses (Stack) Solved a neat stack problem today! 💡 Idea: Track the depth of parentheses and skip the outermost layer of each valid group. ⚡ Time: O(n) 🎯 Key Learning: 👉 Focus on depth rather than structure — simplifies the problem a lot. #DSA #LeetCode #Stack #Coding #ProblemSolving

💬 "The best error message is the one that never shows up." — Thomas Fuchs Great developers don't just fix bugs. They design systems where bugs can't hide. → Validate inputs early → Fail fast and loudly → Write tests before you think you need them Prevent > fix. #SoftwareEngineering #BestPractices #DevQuotes #Coding

Day 2 🚀 Solved: String to Integer (atoi) (LeetCode 8) This one felt like building a parser from scratch. You’re given a string and need to convert it into a 32-bit signed integer while handling multiple edge cases. 💡 Key idea: Process the string step by step — Ignore leading spaces Handle optional sign (+ / -) Extract digits until a non-digit appears The tricky part is handling overflow within 32-bit integer limits. 🔹 Approach: Build the number digit by digit and check for overflow before adding each digit ⏱️ Time Complexity: O(n) 🔗 GitHub: https://lnkd.in/gzueKwNd #DSA #LeetCode #Coding

Day 6 🚀 Solved: Maximum Depth of Binary Tree (LeetCode 104) This is a classic recursion problem on trees. 💡 Key idea: The depth of a tree is 1 + the maximum depth of its left and right subtrees. 🔹 Approach: If the node is null → depth is 0 Recursively calculate depth of left and right Take the maximum and add 1 ⏱️ Time Complexity: O(n) 🔗 GitHub: https://lnkd.in/gz5mBpDx #DSA #LeetCode #Coding