Finding Middle Node in Linked List with Fast & Slow Pointers in Java

✨ Day 30 - K Closest Elements to a Target (Two-Pointer Approach in Java) Worked on a classic array problem today — finding k elements closest to a given target using a clean two-pointer technique. Instead of brute force or sorting by distance, I used a shrinking window approach to keep the solution efficient and interview-friendly. 🧠 What I Did • Took array size and elements as input • Read target value and k • Initialized left and right pointers • Compared distances from the target • Shrunk the window until only k elements remained • Printed the final window 💡 Concepts Strengthened • Two-pointer technique • Absolute difference logic • Window shrinking strategy • Time-efficient array processing 📌 Why This Matters Problems like this test how well you balance logic, efficiency, and clarity. It’s not about writing more code — it’s about writing the right code. Slowly building problem-solving depth, one concept at a time. 🚀 #DSA #Java #TwoPointers #SlidingWindow #ProblemSolving #CodingJourney #LinkedInLearning #DataStructures #DataStructureAndAlgorithm

🚀 Daily DSA Practice – Day 9 | Strings & Hashing (Java) Continuing my structured DSA preparation, today I focused on string problems involving character frequency and hashing, implemented using Java. 📌 Problems Solved (LeetCode): • 242. Valid Anagram – Character frequency comparison using arrays / HashMap • 387. First Unique Character in a String – Frequency tracking with single pass optimization • 383. Ransom Note – Efficient character availability validations. 🎯 Key Learnings: ✔ Practical use of HashMap and frequency arrays ✔ Writing O(n) time complexity solutions ✔ Understanding trade-offs between space vs performance ✔ Improved clarity in handling character-based constraints Consistent practice is reinforcing my ability to translate problem statements into optimized, readable Java code, aligned with industry-level expectations. #DSA #LeetCode #Java #Hashing #ProblemSolving #SoftwareEngineer #BackendDeveloper #InterviewPreparation

day 92/100 #leetcodegrinding The number of rotations equals the index of the minimum element in the array. Using binary search, we can find this efficiently in O(log n) time. 🧠 What I focused on: Identifying the pivot (minimum element) Handling rotated vs non-rotated cases Applying binary search with correct boundaries Writing a clean and efficient Java solution This problem really strengthens understanding of rotated arrays and search logic. Keeping the streak alive 🚀 #DSA #ProblemSolving #Java #BinarySearch #Arrays #LeetCode #CodingPractice #DailyLearning

day 93/100 #leetcodegrind “Find Minimum in a Sorted Rotated Array” problem — a classic example of Binary Search in action. 💡 Key idea: In a rotated sorted array, the minimum element is the pivot. By comparing mid and high elements, we can efficiently narrow the search space to find the minimum in O(log n) time. 🧠 What I practiced: Binary search on rotated arrays Identifying the pivot element efficiently Handling edge cases like non-rotated arrays Writing clean and optimized Java code It’s a simple problem, but it reinforces the power of binary search in non-traditional ways. Rotation? No problem! 🔄🚀 #DSA #ProblemSolving #Java #BinarySearch #Arrays #LeetCode #CodingPractice #DailyLearning

🚀 Day 85 of LeetCode Challenge ✅ Problem: Merge Two Sorted Lists 🔗 https://lnkd.in/g5VY8a3n 💡 Approach: Use a dummy node to simplify list construction Maintain a current pointer to build the merged list Compare nodes from both lists and attach the smaller one Move the pointer forward until one list is exhausted Attach the remaining nodes from the non-empty list ⚡ Performance: ✅ All test cases passed (208 / 208) ⏱ Runtime: 0 ms (Beats 100.00%) 💾 Memory: 44.60 MB 📚 Key Learning: Using a dummy node avoids edge-case handling and leads to cleaner, more readable linked list solutions—especially for merge operations. 🔧 Language: Java 📈 Day 85 complete — consistency is turning effort into skill. #LeetCode #DSA #Java #LinkedList #ProblemSolving #100DaysOfCode #Consistency

Day 29 Today’s problem: LeetCode 153 – Find Minimum in Rotated Sorted Array This problem was a great reminder of how powerful Binary Search can be when applied thoughtfully. Key Takeaways: A rotated sorted array still has structure—you just need to identify it. Comparing mid with right helps decide which half contains the minimum. Achieved O(log n) time complexity by avoiding linear scans. #DSA #Java #LeetCode #BinarySearch #ProblemSolving #CodingJourney #FindMinimuminRotatedSortedArraySoln

Just solved today’s LeetCode Daily Question in Java. Problem: Given multiple axis-aligned squares (with possible overlaps), find the minimum y-coordinate of a horizontal line such that the union area above the line equals the union area below it. Approach used: Sweep Line (Y-axis events) to process active square intervals Interval merging on X-axis to compute union width at each y-slab Built the total union area, then used a binary search on y to locate the balance point within 1e-5 precision This was a great practice for combining computational geometry concepts with efficient implementation details. #LeetCode #Java #DSA #SweepLine #BinarySearch #ProblemSolving #CompetitiveProgramming

🚀Day 14 of #120DaysOfCode 📌 Problem: Matrix Reshape(566) 📌 Language: Java 🔍Approach 1. Check if Reshape is possible 2. Traverse the original matrix in row order 3. Mapping logic ⏱️ Time and Space Complexity Time Complexity: O(m x n) Space complexity: O(r x c) 🔥One problem closer to mastery #120DaysOfCode #Day14 #Java #Array #Leetcode #ProblemSolving #Consistency #LearningEveryday #LearningPublic #DSA

🚀Day 7 of #120DaysOfCode 📌 Problem: Find all numbers disappeared in an Array(448) 📌 Language: Java 🔍Approach: Using HashSet . Store all elements of nums in a set . Loop from 1 to n . If a number is not in the set --> it's missing ⏱️ Time and Space Complexity Time Complexity: O(n) Space complexity: O(n) 🔥One problem closer to mastery #120DaysOfCode #Day6 #Java #Array #Leetcode #ProblemSolving #Consistency #LearningEveryday #LearningPublic #DSA

🚀 Day 52 of #100DaysOfCode Solved LeetCode Problem #712 – Minimum ASCII Delete Sum for Two Strings. This problem focused on minimizing the total ASCII value of deleted characters to make two strings equal. A classic dynamic programming challenge that required carefully defining states and transitions for optimal substructure. Key Learnings: -> Modeled the problem using DP on string indices -> Handled base cases when one string is fully consumed -> Used memoization to avoid overlapping subproblems Strengthened understanding of string DP and cost-based optimization Language Used: Java -> Runtime: 34 ms (Beats 7.60%) -> Memory: 50.39 MB Consistent practice, deeper DP intuition, and steady progress 🚀 #LeetCode #DynamicProgramming #Java #ProblemSolving #100DaysOfCode