Finding Min in Rotated Sorted Array II on LeetCode with Binary Search

🚀 Day 39 of #100DaysOfCode Solved 80. Remove Duplicates from Sorted Array II on LeetCode 🔢 🧠 Key Insight: The array is already sorted, and we need to ensure that each element appears at most twice, modifying the array in-place. ⚙️ Approach: 🔹Maintain a pointer i representing the position to place the next valid element 🔹Start iterating from index 2 🔹For each element nums[j], compare it with nums[i] 🔹If they are different, place the element at nums[i + 2] and move the pointer forward This ensures that no element appears more than twice while maintaining the sorted order. ⏱️ Time Complexity: O(n) 📦 Space Complexity: O(1) #100DaysOfCode #LeetCode #DSA #Arrays #TwoPointers #Java #ProblemSolving #InterviewPrep #LearningInPublic

𝐃𝐚𝐲 𝟓𝟔 – 𝐃𝐒𝐀 𝐉𝐨𝐮𝐫𝐧𝐞𝐲 | 𝐀𝐫𝐫𝐚𝐲𝐬 🚀 Today’s problem focused on finding a peak element using binary search. 𝐏𝐫𝐨𝐛𝐥𝐞𝐦 𝐒𝐨𝐥𝐯𝐞𝐝 • Find Peak Element 𝐀𝐩𝐩𝐫𝐨𝐚𝐜𝐡 • Used binary search instead of linear scan • Compared the middle element with its next element Logic: • If nums[mid] > nums[mid + 1] → peak lies on the left side (including mid) • Else → peak lies on the right side • Continued until left == right 𝐊𝐞𝐲 𝐋𝐞𝐚𝐫𝐧𝐢𝐧𝐠𝐬 • Binary search can be applied on patterns, not just sorted arrays • A peak always exists due to problem constraints • Comparing adjacent elements helps determine direction • Reducing the search space is the key idea 𝐂𝐨𝐦𝐩𝐥𝐞𝐱𝐢𝐭𝐲 • Time: O(log n) • Space: O(1) 𝐓𝐚𝐤𝐞𝐚𝐰𝐚𝐲 Binary search is not about sorted arrays — it’s about eliminating half of the search space using logic. 56 days consistent 🚀 On to Day 57. #DSA #Arrays #BinarySearch #LeetCode #Java #ProblemSolving #DailyCoding #LearningInPublic #SoftwareDeveloper

🚀 Day 61 of #100DaysOfCode Solved 101. Symmetric Tree on LeetCode 🔗 🧠 Key Insight: A tree is symmetric if it is a mirror of itself 👉 Left subtree is a mirror of right subtree ⚙️ Approach (Recursive Mirror Check): 1️⃣ Start by comparing: 🔹 root.left and root.right 2️⃣ If both are null → ✅ symmetric 3️⃣ If one is null → ❌ not symmetric 4️⃣ If values differ → ❌ not symmetric 5️⃣ Recursively check mirror condition: 🔹 left.left with right.right 🔹 left.right with right.left 6️⃣ Return: 👉 isMirror(left.left, right.right) && isMirror(left.right, right.left) ⏱️ Time Complexity: O(n) 📦 Space Complexity: O(h) (recursion stack) #100DaysOfCode #LeetCode #DSA #BinaryTree #Recursion #DFS #Java #InterviewPrep #CodingJourney

🔥 Day 98 of #100DaysOfCode Today’s challenge: LeetCode – Search in Rotated Sorted Array II 🔄🔍 📌 Problem Summary You are given a rotated sorted array that may contain duplicates. Your task is to determine whether a target exists in the array. Example: Input: nums = [2,5,6,0,0,1,2], target = 0 Output: true 🧠 Approach Used: Linear Search In this implementation, we simply iterate through the array and check if the element matches the target. ⚙️ Logic for(int i = 0; i < nums.length; i++){ if(nums[i] == target){ return true; } } return false; 💡 Explanation Traverse the array from start to end If the target is found → return true If the loop finishes → return false ⏱ Time Complexity: O(n) 💾 Space Complexity: O(1) 🚀 Performance Runtime: 0 ms Memory: 44.9 MB 🧠 Learning This problem is a variation of Search in Rotated Sorted Array, but with duplicates allowed. While a Binary Search solution exists, duplicates can break the strict ordering and make the logic more complex. A simple linear scan ensures correctness in all cases. Only 2 days left to complete #100DaysOfCode 🚀 Almost at the finish line! On to Day 99 🔥 #100DaysOfCode #LeetCode #Java #DSA #CodingJourney #InterviewPrep

Day 68/100 Completed ✅ 🚀 Solved LeetCode – Split Array Largest Sum (Java) ⚡ Applied an efficient Binary Search on Answer approach to split the array into k subarrays such that the largest subarray sum is minimized. Instead of trying all possible splits, optimized the solution by searching within the range of maximum element and total sum, and validating using a greedy strategy. 🧠 Key Learnings: Identifying binary search applicability in partition-based problems Defining search space using max element (lower bound) and total sum (upper bound) Using greedy logic to check feasibility of splitting into k subarrays Minimizing the maximum subarray sum through efficient validation 💯 This problem strengthened my understanding of partition problems and reinforced how binary search can be used for optimization rather than direct searching. 🔗 Profile: https://lnkd.in/gaJmKdrA #leetcode #datastructures #algorithms #java #binarysearch #problemSolving #100DaysOfCode

𝐃𝐚𝐲 𝟓𝟒 – 𝐃𝐒𝐀 𝐉𝐨𝐮𝐫𝐧𝐞𝐲 | 𝐀𝐫𝐫𝐚𝐲𝐬 🚀 Today’s problem focused on finding the minimum element in a rotated sorted array using binary search. 𝐏𝐫𝐨𝐛𝐥𝐞𝐦 𝐒𝐨𝐥𝐯𝐞𝐝 • Find Minimum in Rotated Sorted Array 𝐀𝐩𝐩𝐫𝐨𝐚𝐜𝐡 • Used binary search to reduce the search space • Compared the middle element with the rightmost element Logic: • If nums[mid] > nums[right] → minimum lies in the right half • Else → minimum lies in the left half (including mid) • Continued until left meets right 𝐊𝐞𝐲 𝐋𝐞𝐚𝐫𝐧𝐢𝐧𝐠𝐬 • Rotated arrays require a modified binary search • Comparing with boundary elements helps identify the sorted half • Binary search is not only for exact matches • Reducing the search space is the core idea 𝐂𝐨𝐦𝐩𝐥𝐞𝐱𝐢𝐭𝐲 • Time: O(log n) • Space: O(1) 𝐓𝐚𝐤𝐞𝐚𝐰𝐚𝐲 Binary search is about asking the right question — not just finding the middle. 54 days consistent 🚀 On to Day 55. #DSA #Arrays #BinarySearch #LeetCode #Java #ProblemSolving #DailyCoding #LearningInPublic #SoftwareDeveloper

🚀 Day 84/100 – 𝐒𝐞𝐚𝐫𝐜𝐡 𝐢𝐧 𝐑𝐨𝐭𝐚𝐭𝐞𝐝 𝐒𝐨𝐫𝐭𝐞𝐝 𝐀𝐫𝐫𝐚𝐲 𝐈𝐈  🔍  𝐊𝐞𝐲 𝐋𝐞𝐚𝐫𝐧𝐢𝐧𝐠: Binary search works great on sorted arrays, but duplicates introduce ambiguity — making it harder to decide which half is sorted. 💡 𝐂𝐨𝐫𝐞 𝐈𝐝𝐞𝐚: Use modified binary search Identify the sorted half Handle duplicates by shrinking the search space ⚡ 𝐀𝐩𝐩𝐫𝐨𝐚𝐜𝐡: Find 𝐦𝐢𝐝 If 𝐭𝐚𝐫𝐠𝐞𝐭 𝐟𝐨𝐮𝐧𝐝 → 𝐫𝐞𝐭𝐮𝐫𝐧 𝐭𝐫𝐮𝐞 𝐇𝐚𝐧𝐝𝐥𝐞 𝐝𝐮𝐩𝐥𝐢𝐜𝐚𝐭𝐞𝐬 (𝐥𝐨𝐰++) Check which half is sorted Narrow down search accordingly #Day84 #100DaysOfCode #Java #DSA #LeetCode #BinarySearch #CodingJourney

🚀 #100DaysOfCode | Day 47 🔍 Solved: Find Minimum in Rotated Sorted Array Today I explored another interesting variation of Binary Search. Instead of searching for a target, the goal was to find the minimum element in a rotated sorted array. 💡 Key Insight: By comparing the middle element with the last element, we can determine which half contains the minimum value. Approach: ✔ Used Binary Search to achieve O(log n) time complexity ✔ Compared mid with end to identify the unsorted portion ✔ Narrowed down the search space efficiently What I Learned: This problem helped me understand how binary search can be applied beyond simple searching—especially in rotated and partially sorted arrays. #Java #DSA #LeetCode #BinarySearch #CodingJourney #ProblemSolving #TechSkills

Day 16/100 – LeetCode Challenge Problem: Merge Sorted Array Today’s problem involved merging two sorted arrays into one sorted array. Approach: Created a temporary array of size m + n Used two pointers to compare elements from both arrays Inserted the smaller element into the new array Copied remaining elements if any array still had values Finally copied the merged result back into nums1 Complexity: Time: O(m + n) Space: O(m + n) Concepts Practiced: Two-pointer technique Array traversal Merging sorted arrays #100DaysOfCode #LeetCode #DSA #Java #Arrays #ProblemSolving #CodingJourney

#Day67 of my second #100DaysOfCode Today’s problem pushed me to think carefully about comparisons and sorting logic. DSA • Solved Reverse Pairs (LeetCode 493) — count pairs (i, j) such that i < j and nums[i] > 2 * nums[j] • Brute force: check every pair using nested loops → O(n²) time • Optimal approach: Modified Merge Sort to count valid pairs during merge → O(2n log n) time, O(n) space • Key insight: count pairs across the left and right halves before merging. Another reminder of how divide-and-conquer + merge sort patterns appear in many hard problems. #DSA #Algorithms #LeetCode #MergeSort #Java #100DaysOfCode #WomenWhoCode #BuildInPublic #LearningInPublic