Java Scanner nextLine() Bug Fix: Consume the Ghost

Day25 - LeetCode Journey Solved LeetCode 344: Reverse String in Java ✅ This was a simple problem on the surface, but it perfectly highlights how powerful clean logic can be. The goal was to reverse a string in-place using O(1) extra space, which means no extra arrays and no shortcuts. Just pure two-pointer logic. Using the left and right pointers and swapping characters step by step felt very satisfying. It’s one of those patterns that looks small but appears everywhere in interviews and real-world problems. Mastering this makes many string and array problems much easier later on. What I liked about this problem is how it teaches efficiency. Instead of creating new memory, we directly modify the existing array. That mindset of optimizing space is extremely important in DSA. Key takeaways: • Strong practice of the two-pointer technique • In-place operations with constant extra space • Clean and readable swapping logic • Reinforced fundamentals of string manipulation ✅ Accepted successfully ✅ 0 ms runtime with optimal performance Sometimes the simplest problems build the strongest foundations. Consistency with basics is what makes complex problems feel easier later 💪 #LeetCode #DSA #Java #Strings #ProblemSolving #Algorithms #CodingJourney #InterviewPreparation #TwoPointers #Consistency #DailyPractice

LeetCode Daily — Problem #3794: Reverse String Prefix Today’s challenge was a fun string manipulation task: Problem: Given a string s and an integer k, reverse the first k characters and return the resulting string. Example: Input: s = "abcd", k = 2 Output: "bacd" Approach: I converted the string to a character array, reversed the first k characters using a loop, and then appended the rest. Here's the Java solution:✅ Result: Accepted with 0 ms runtime! Takeaway: This problem reinforced how simple logic and clean iteration can solve string-based challenges efficiently. It’s a great reminder that even “Easy” problems can sharpen your fundamentals. #LeetCode #Java #StringManipulation #CodingChallenge #100DaysOfCode #ProblemSolving #LinkedInLearning

#Day 63: LeetCode 1984 - Minimum Difference Between Highest and Lowest of K Scores Code:- import java.util.Arrays; class Solution {   public int minimumDifference(int[] nums, int k) {     // Step 1: Handle the edge case where only one score is picked     if (k == 1) return 0;     // Step 2: Sort the scores to bring close values together     Arrays.sort(nums);           int minDiff = Integer.MAX_VALUE;           // Step 3: Slide a window of size k through the array     // The window starts at 'i' and ends at 'i + k - 1'     for (int i = 0; i <= nums.length - k; i++) {       int currentDiff = nums[i + k - 1] - nums[i];               // Step 4: Update the global minimum difference       if (currentDiff < minDiff) {         minDiff = currentDiff;       }     }           return minDiff;   } } #The Strategy: ->Sort the scores to align them by magnitude. ->Apply a Sliding Window of size $k$ to look at every possible 'cluster' of scores. ->Calculate the spread (Max - Min) for each cluster and capture the minimum. #100DaysOfCode #Java #SoftwareEngineering #Algorithms #LeetCode #SDE #ProblemSolving #SlidingWindow"

Day26 - LeetCode Journey Solved LeetCode 345: Reverse Vowels of a String in Java ✅ This problem was a fun twist on the classic string reversal pattern. Instead of reversing the whole string, the focus was only on vowels, which makes you think a little more carefully about pointer movement and conditions. Using the two-pointer approach here felt really clean. One pointer moves from the start, the other from the end, and both skip non-vowel characters until a valid swap is possible. Simple logic, but very effective. It’s a great example of how a small condition change can turn an easy problem into a nice logical exercise. What I enjoyed most was how this problem strengthens selective traversal. You’re not touching every character blindly, you’re filtering and acting only when needed. That mindset is very useful in optimizing solutions. Key takeaways: • Strong practice of the two-pointer technique • Efficient handling of character filtering • Clean in-place swapping logic • Better understanding of conditional traversal ✅ Solution accepted successfully ✅ Solid performance with clean and readable code Problems like this make string manipulation feel more intuitive and structured. One more step forward in sharpening fundamentals 💪 #LeetCode #DSA #Java #Strings #TwoPointers #ProblemSolving #Algorithms #CodingJourney #InterviewPreparation #Consistency #DailyPractice

📁 File Handling 🌊ByteStreams = flow of data as bytes 👉 Byte streams handle raw bytes 🧱 👉 FileInputStream → read 📥 👉 FileOutputStream → write 📤 👉 read() returns -1 at EOF 🛑EndOfFile 👉 Temp variable avoids skipping bytes 🔁 👉 String ➝ getBytes() → byte[] 🔄 👉 Append mode using true ➕ • read() returns 0–255 or -1, so return type is int • int -1 allows JVM to safely signal EndOfFile 🧠 java.io.File 📦 is the package that imports File Class ⚠️ Why try-catch exists • Files live outside JVM 💽 • JVM can’t guarantee file exists, path is valid, or permission is granted 🚫 • So Java forces you to handle risk using checked exceptions 🛡️ • Byte streams → raw data 🧱 • Character streams → text + encoding 📝 👉 Byte streams move raw bytes between JVM and external systems of any format Byte streams deal with bytes, character streams deal with characters using encoding. GitHub Link: https://lnkd.in/eur5pBx4 🔖Frontlines EduTech (FLM) #Java #FileHandling #Streams #BackendDevelopment #JVM #LearningInPublic #ResourceManagement #AustraliaJobs #SwitzerlandJobs #NewZealandJobs #USJobs #BackendDevelopment #Programming

🚀 Day 21 of my DSA Journey (LeetCode + Java) Today’s practice focused on Array Manipulation + Counting Frequency problems. All three questions looked simple at first, but each required a deeper thought process to get the most optimized solution. ✅ Problems Solved Today LC 66 – Plus One LC 88 – Merge Sorted Array LC 1189 – Maximum Number of Balloons 🧠 My Experience Solving These: 🔸 66. Plus One This problem was trickier than I expected. Initially, I solved it in a non-optimized way. Then I realized the key insight: Traverse from the end If digit < 9, just increment and return If digit is 9 → make it 0 and continue If all digits are 9 → create new array with leading 1 Once I understood this, I solved it in one single loop—clean and efficient. 🔸 88. Merge Sorted Array My first approach used two loops and sorting, but it was: Extra time Not optimal Then I optimized it by using three pointers: i at the end of arr1 j at the end of arr2 k at the final position Compare & place larger element → move pointers. Finally append remaining elements from arr2. This method was fully optimized (O(n)) without any extra space. 🔸 1189. Maximum Number of Balloons This one was fun! I used a HashMap to count frequency of characters. The tricky part was: How to divide counts correctly for repeated characters like 'l' and 'o' After several dry runs, the logic became clear: Count freq of each char in text Count required freq for word “balloon” Divide actual/required → minimum of all divisions = answer A clean and optimal solution. 📌 Key Takeaway Today Even simple array problems can become tricky if we miss the pattern. Today I reinforced: ✔ Think from the end for digit problems ✔ Use three pointers for merging arrays ✔ Frequency-based problems → always check min(actual/required) ✔ Dry run is your best friend Step-by-step progress every day is building my confidence and logical thinking. 💪 On to Day 22! 🚀 #DSA #LeetCode #Java #Arrays #HashMap #ProblemSolving #CodingJourney #Consistency #LearningDaily

Day22 - LeetCode Journey Solved LeetCode 242: Valid Anagram in Java ✅ This problem was a nice reminder of how simple ideas can lead to clean and effective solutions. Checking whether two strings are anagrams really comes down to understanding character frequency and order. By sorting both strings and comparing them character by character, the logic becomes very straightforward and easy to follow. What I liked about this problem is how it strengthens fundamentals of string handling and arrays. It also shows how preprocessing data can simplify the main comparison logic. Small steps like converting strings to character arrays and sorting them make the solution both readable and reliable. Key takeaways: • Better understanding of string to array conversion • Using sorting as a tool to simplify comparisons • Writing clean and minimal logic • Strengthening basics of string manipulation ✅ All test cases passed successfully ✅ Logic kept simple and efficient ✅ Another step forward in building strong DSA foundations Consistency with such problems really builds confidence over time 💪 #LeetCode #Java #DSA #Strings #ValidAnagram #ProblemSolving #CodingJourney #InterviewPreparation #Algorithms #Consistency #LearningEveryday

Just solved **LeetCode 219: Contains Duplicate II** (Easy) using a clean **sliding window + HashSet** approach in Java! 🚀 The key insight: Maintain a set of at most (k+1) recent elements. If you encounter a duplicate before sliding out older ones, the indices are guaranteed to be ≤ k apart. java class Solution { public boolean containsNearbyDuplicate(int[] nums, int k) { Set<Integer> set = new HashSet<>(); for (int i = 0; i < nums.length; i++) { // If we've already seen this number in the current window, it's a duplicate! if (set.contains(nums[i])) { return true; } // Add the current number to the set (window) set.add(nums[i]); // If the window is too big (more than k+1 elements), remove the oldest one if (set.size() > k) { set.remove(nums[i - k]); } } return false; // No nearby duplicates found } } - Time: O(n) - Space: O(k) What's your favorite sliding window problem? Drop it below! 👇 #LeetCode #Coding #DataStructures #Algorithms #Java #SystemDesign #Tech #InterviewPrep

50 lines of code vs. 1 line. Who wins? 🥊 If you’re still writing getters, setters, constructors, and toString methods manually in 2026, you are working too hard. Java Records changed the game by killing "Boilerplate Hell." It turns a massive, messy POJO into a single, elegant line of code. In my latest blog post, I break down: ✅ Why "Data as Data" is better than "Data as Behavior." ✅ The "Freebies" you get from the compiler. ✅ Real-world scenarios where Records shine. Read the full breakdown here: 👇 https://lnkd.in/gUkyPU8c #Java #CleanCode #SoftwareEngineering #BackendDevelopment #JavaRecords #ProgrammingTips

Thread safety is not a keyword. It’s a behavior. Code that works perfectly in a single-threaded program can break the moment multiple threads touch shared data — and often only sometimes. In my latest video, I explain: • What thread safety really means • Why shared mutable state causes most bugs • How to think about writing thread-safe code in Java If you’ve ever seen a bug disappear after adding logs, you’ve felt this problem. 🎥 Link in comments #Java #ThreadSafety #Multithreading #JavaConcurrency #SoftwareEngineering