"Day 82 of #100DaysOfLeetCode: Find Missing Numbers in Array"

On Day 298 of my #300daysofcode challenge, I'm sharing my solution to LeetCode Problem 74, "Search a 2D Matrix." This problem is a classic demonstration of adapting the Binary Search algorithm to a 2D structure. My video provides a clear walkthrough of the key optimization: mapping $(row, col)$ indices to a single linear index to perform a fast, $O(\log(M \cdot N))$ search. This is a valuable skill for technical interviews and efficient matrix manipulation. #DataStructures #Algorithms #LeetCode #CodingInterview #Programming #BinarySearch #300daysofcode

On Day 295 of my #300daysofcode challenge, I'm sharing my solution to LeetCode Problem 981, "Time Based Key-Value Store." This problem requires designing a specialized data store for version control. My video provides a clear walkthrough of the optimal design: using a HashMap to quickly find the key and then applying Binary Search on the timestamps to retrieve the correct historical value. This is a valuable skill for advanced data structure implementation and system design interviews. #DataStructures #Algorithms #LeetCode #CodingInterview #Programming #SystemDesign #300daysofcode

💻 Day 34 of #100DaysOfLeetCode Today’s Challenge: 83. Remove Duplicates from Sorted List 🔹 Problem: Given the head of a sorted linked list, delete all duplicates such that each element appears only once. Return the linked list sorted as well. Key Insight: Because the list is already sorted, duplicates will always be adjacent—this allows us to remove them in a single pass using pointer manipulation. 🔍 Approach: Traverse the list using a pointer. Compare current node with the next node. If values are equal → skip the next node by linking to the next of next. Otherwise → move forward. 🕒 Time Complexity: O(n) 📦 Space Complexity: O(1) ✨ Key Takeaway: This problem reinforces the importance of pointer manipulation and understanding how memory references work in linked lists. A simple check can eliminate duplicates efficiently without using extra space. Link:[https://lnkd.in/gsjVxHXM] #100DaysOfLeetCode #Day34 #LeetCode #ProblemSolving #DSA #Algorithms #LinkedList #CodingChallenge #CodeNewbie #InterviewPreparation #SoftwareEngineering #Programming #CodingCommunity #TechCareers #CareerGrowth #ArjunInfoSolution

On Day 288 of my #300daysofcode challenge, I'm sharing my solution to LeetCode Problem 3354, "Maximum Length of Semi-Decreasing Subarrays II." This problem requires optimizing a brute-force approach. My video provides a clear walkthrough of the efficient Two-Pointer technique (or Monotonic Stack), which is a valuable skill for technical interviews and a great way to think about improving time complexity. #DataStructures #Algorithms #LeetCode #CodingInterview #Programming #Optimization #300daysofcode

🧩 Day 64 of #100DaysOfCode 🧩 🔹 Problem: Remove All Adjacent Duplicates in String – LeetCode ✨ Approach: Used a stack-based approach to efficiently remove adjacent duplicates. For each character, if it matches the stack’s top element, pop it — otherwise, push it. A simple yet powerful way to process strings in O(n) time while maintaining clean logic. ⚡ 📊 Complexity Analysis: Time Complexity: O(n) — each character is processed once Space Complexity: O(n) — for the stack and output string ✅ Runtime: 23 ms (Beats 54.52%) ✅ Memory: 45.26 MB (Beats 85.43%) 🔑 Key Insight: Sometimes, solving problems isn’t about brute force — it’s about using the right data structure to make every step count. 💡 #LeetCode #100DaysOfCode #ProblemSolving #DSA #Stack #StringManipulation #CleanCode #CodingChallenge #AlgorithmDesign #LogicBuilding #CodeJourney #Programming

On Day 302 of the coding journey, I'm sharing my solution to LeetCode Problem 528, "Random Pick with Weight." This problem requires designing a data structure for weighted random selection. My video provides a clear walkthrough of the optimal strategy: using a Prefix Sums array to map weights to cumulative ranges, then performing a fast Binary Search to find the corresponding index. This is a valuable skill for system design and advanced data structure implementation. #DataStructures #Algorithms #LeetCode #CodingInterview #Programming #BinarySearch #PrefixSums

On Day 299 of my #300daysofcode challenge, I'm sharing my solution to LeetCode Problem 275, "H-Index II." The key to solving this problem efficiently is recognizing that the sorted input array creates a monotonic property that enables Binary Search. My video provides a clear walkthrough of the $O(\log N)$ search logic, a highly valued skill for technical interviews focused on algorithmic optimization. #DataStructures #Algorithms #LeetCode #CodingInterview #Programming #BinarySearch #300daysofcode

🚀 Today I practiced one of the most important Linked List problems — Sorting a Linked List efficiently. Instead of converting the list into an array (which increases extra memory usage), I implemented Merge Sort directly on the linked list. 🔍 Why Merge Sort for Linked List? Linked lists don’t have random indexing. Merge Sort works naturally by rearranging pointers. No need of extra space for arrays. 🎯 Result: Time Complexity: O(n log n) Space Complexity: O(log n) due to recursion Stable & Clean Solution 💡 What I learned: Using slow–fast pointer technique to find the middle of the list. Splitting the linked list into two halves efficiently. Merging two sorted linked lists without extra memory. Writing cleaner, structured logic improves readability a LOT. Everyday small progress really compounds. Trying to solve at least one challenge daily 💪 #ConsistencyWins #leetcode #dsa #linkedlist #algorithms #programming #cpp  #softwareengineering #codingjourney #learningeveryday #100daysofcode

On Day 293 of my #300daysofcode challenge, I'm sharing my solution to LeetCode Problem 436, "Find Right Interval." This problem requires optimizing a search over intervals, which we solve efficiently by combining sorting by start time with Binary Search. My video provides a clear walkthrough of this $O(N \log N)$ approach, a valuable skill for technical interviews and mastering interval manipulation. #DataStructures #Algorithms #LeetCode #CodingInterview #Programming #BinarySearch #300daysofcode

💻 Day 33 of #100DaysOfLeetCode 🔗 Today’s Challenge: Intersection of Two Linked Lists 🔹 Problem: Find the node at which two singly linked lists intersect. If the two linked lists do not intersect, return null. This is a classic problem to test understanding of linked list structure, pointer manipulation, and memory reference. 🔍 Naive Approach: Use nested loops to compare each node in list A with each node in list B. Time Complexity: O(m × n) Not efficient and not recommended for large lists. 🚀 Optimized Two-Pointer Approach: Use two pointers that traverse both lists. When one pointer reaches the end, redirect it to the head of the other list. If they intersect, the pointers will meet at the intersection node. If not, both will reach null simultaneously. 🕒 Time Complexity: O(m + n) 📦 Space Complexity: O(1) Link:[https://lnkd.in/gyTB4GqG] #100DaysOfLeetCode #Day33 #LeetCode #ProblemSolving #Algorithms #DSA #LinkedList #CodingChallenge #CodeNewbie #InterviewPreparation #SoftwareEngineering #Programming #CodingCommunity #TechCareers #CareerGrowth #ArjunInfoSolution