Merging Intervals in Java with LeetCode

🚀 Day 29 of 100 Days of LeetCode 📘 Problem: Combination Sum 💻 Language: Java ✅ Status: Accepted — Runtime ⚡ 2 ms (Beats 86%) Today’s problem was all about backtracking — exploring all possible combinations to reach a target sum. It’s a perfect blend of recursion, decision-making, and pruning unnecessary paths 🧠 ✨ Key Learnings: Backtracking is like exploring a maze — try, backtrack, and try again until you find the exit 🌀 Each recursive call represents a “choice point” — include or skip the element Clean recursion with controlled base cases leads to clarity and precision This problem reminded me how persistence works in both code and life: 💬 “Sometimes, the path to the solution is not straightforward — you just need to keep exploring.” #Day29 #100DaysOfCode #LeetCode #Java #Backtracking #Recursion #DSA #ProblemSolving #CodingJourney #SoftwareDevelopment #KeepLearning #CodeEveryday

🚀 Day 26 of 100 Days of LeetCode 📘 Problem: Search a 2D Matrix 💻 Language: Java ✅ Status: Accepted — Runtime: ⚡ 0 ms (Beats 100%) Today’s problem focused on searching efficiently within a 2D matrix — a great exercise for understanding nested loops, traversal logic, and time optimization. While this version used a simple brute-force approach, it served as a good refresher on matrix iteration patterns before moving on to more optimized binary search techniques in 2D grids. ✨ Key Learnings: Matrix traversal can be intuitive when visualized 🔢 Always consider both brute-force and optimized approaches — understanding both is key to depth of knowledge Writing clean, readable code matters as much as optimizing it Each problem solved is another small brick in the foundation of strong problem-solving skills 💪 #Day26 #100DaysOfCode #LeetCode #Java #ProblemSolving #DSA #CodingJourney #SoftwareDevelopment #Matrix #KeepLearning #CodeEveryday

🚀 Day 27 of 100 Days of LeetCode 📘 Problem: Generate Parentheses 💻 Language: Java ✅ Status: Accepted — Runtime: ⚡ 0 ms (Beats 100%) Today’s challenge focused on backtracking, one of the most elegant and powerful problem-solving techniques in DSA. The task was to generate all possible valid combinations of parentheses — a perfect test of recursion and logical constraints 🧩 ✨ Key Learnings: Backtracking is about exploring all possibilities, then undoing choices when needed 🔄 Understanding base cases clearly makes recursion much easier Clean recursive structures lead to elegant and efficient solutions This problem reinforced one important principle — 🧠 “Sometimes, going back is the only way to move forward — both in code and in life.” #Day27 #100DaysOfCode #LeetCode #Java #Backtracking #Recursion #ProblemSolving #CodingJourney #DSA #SoftwareDevelopment #KeepLearning #CodeEveryday

🌟 Day 86 of #100DaysOfCodingChallenge 🌟 🚀 Problem: 561. Array Partition 💻 Language: Java Today’s challenge was about maximizing the sum of the minimum values in n pairs formed from an array of 2n integers. 🧩 Approach: 1️⃣ Sort the array in ascending order. 2️⃣ Take every alternate element (starting from index 0). 3️⃣ Add them up — this gives the maximum possible sum of mins in all pairs. 🧠 Key Insight: When the array is sorted, pairing adjacent elements ensures the smallest numbers are always matched optimally, leading to the maximum possible result. 📊 Example: Input → [1,4,3,2] Sorted → [1,2,3,4] Pairs → (1,2), (3,4) Output → 4 ✅ ✨ Learning: Sometimes the simplest approach — sorting and selecting — can yield the most optimal result! #Day86 #LeetCode #Java #100DaysOfCode #CodingChallenge #ProblemSolving #ArrayPartition #DSA #WomenInTech #SathyabamaUniversity

🌟 Day 93 of #100DaysOfCodingChallenge 🌟 🔹 Problem: 442. Find All Duplicates in an Array 🔹 Platform: LeetCode 🔹 Language: Java 🔹 Difficulty Level: Medium 🧩 Problem Statement: Given an integer array nums containing numbers from 1 to n, find all the elements that appear twice in the array. 💡 Intuition: To identify duplicates efficiently, I used two HashSets — one to store visited elements and another to store duplicates when an element is already seen. This method makes the solution concise and easy to understand while maintaining good performance. ✅ Time Complexity: O(n) ✅ Space Complexity: O(n) 🚀 Key Takeaway: Sometimes, clarity and simplicity in code matter more than optimization — this approach is easy to implement and perfectly suitable for most scenarios. #Day93 #LeetCode #100DaysOfCode #Java #ProblemSolving #CodingChallenge #DSA #LearnByCoding #WomenInTech

Day 46 of #100DaysOfLeetCode Challenge 🚀Today’s Problem: Remove Duplicate Letters (LeetCode - Medium) Language: Java In this problem, the goal is to remove duplicate letters from a string such that every letter appears once and the result is the smallest lexicographical order possible. Concepts Covered: Stack for maintaining order Greedy approach for smallest lexicographical sequence Tracking last occurrence index of each character Boolean array to keep track of visited characters Key Takeaways: Understanding when to remove elements from the stack is crucial for optimal ordering. The combination of stack + greedy ensures both uniqueness and lexicographical minimality. #100DaysOfCode #LeetCode #Java #ProblemSolving #CodingChallenge #DSA #DevelopersJourney

🚀 Day 20 of #100DaysOfLeetCode 💡 Problem: Gray Code Today’s challenge was all about generating the Gray Code sequence, a fascinating binary numbering system where only one bit changes between consecutive numbers. 🧠 Concept: Gray codes are widely used in digital communication and error correction, ensuring minimal transition errors between binary states. 🔍 Key takeaway: Bit manipulation + recursion = elegant solution ✨ 💻 Languages used: Java #LeetCode #100DaysOfCode #ProblemSolving #CodingChallenge #Java #GrayCode #DSA #BitManipulation

#Day403_DSA:Today I learned the LeetCode problem "Minimum Number of Operations to Make Array Empty". This question helped me understand how to efficiently use a PriorityQueue and a lazy subtraction technique to minimize operations. Instead of modifying every element, we can track the cumulative subtraction value to optimize performance. It was a great exercise in combining heap logic with mathematical thinking — improving both problem-solving speed and code efficiency. #LeetCode #Java #DSA #PriorityQueue #LearningJourney #RajVikramaditya #TakeUForward

🧩 Day 79 of #100DaysOfCode Today’s problem: LeetCode 3370 – Smallest Number With All Set Bits 💡 The challenge was to find the smallest number greater than or equal to n whose binary representation contains only set bits (1s). 💻 Language: Java ⚙️ Approach: Used bitwise operations to identify numbers whose binary form contains all 1s. The key condition used: (x & (x + 1)) == 0 This ensures that the number has all bits set. ✅ Result: Runtime – 0 ms, beating 100% of Java submissions! ⚡ 📈 Learning: This problem improved my understanding of bit manipulation and binary operations — core concepts for optimizing code performance. #Day79 #LeetCode #100DaysOfCode #CodingChallenge #JavaProgramming #ProblemSolving #BitManipulation #DeveloperJourney #CodeEveryday

💻 LeetCode 50 Days Challenge — Day 8: Median of Two Sorted Arrays Day 8 of my #LeetCode50DaysChallenge ✅ Today’s problem was about finding the median of two sorted arrays — Median of Two Sorted Arrays ✨ 🧩 Problem: Given two sorted arrays nums1 and nums2, return the median of the two sorted arrays. The challenge was to merge them efficiently and then determine the middle value(s). 💡 Approach: I used Java 8 Streams to merge both arrays in a single line using IntStream.concat(), followed by Arrays.sort() to sort the combined array. Finally, I calculated the median by checking if the array length is even or odd. ⏱️ Time Complexity: O((m + n) log (m + n)) (due to sorting) 📊 Example: Input: nums1 = [1, 2], nums2 = [3, 4] Output: 2.5 Each day, I’m getting more comfortable with cleaner and modern Java techniques like Streams — small steps toward writing concise and efficient code 🚀 #LeetCode #CodingChallenge #Day8 #ProblemSolving #Java #SoftwareDevelopment #Consistency #50DaysOfCode