Mastering Frequency Patterns in JavaScript with HashMap

Today I finally understood how JavaScript actually stores data in memory — and it changed the way I look at code. Earlier, I used to just write variables and functions without thinking much about what’s happening behind the scenes. But now it makes a lot more sense: Primitive values (like numbers, strings, booleans) are stored directly in memory Reference types (like arrays and objects) are stored differently — the variable holds a reference, not the actual value That’s why things like this behave unexpectedly sometimes: Copying objects doesn’t create a real copy Changing one reference can affect another Understanding this cleared up a lot of confusion I had while debugging. Still learning, but this felt like a small breakthrough Hitesh Choudhary Piyush Garg Chai Code #JavaScript #WebDevelopment #100DaysOfCode #LearningInPublic

Day 04 of Learning JavaScript Deep Today’s topic looked simple… but turned out to be powerful Traversing an Array - Visiting each element one by one. Example: let arr = [10, 20, 30, 40]; for (let i = 0; i < arr.length; i++) { console.log(arr[i]); } 🧠 Key understanding: Arrays start at index 0 End at length - 1 One mistake can break logic 👇 for (let i = 0; i <= arr.length; i++) { console.log(arr[i]); // undefined at end ❌ } 💭 Simple thought: “Array is just data… Traversal is how you understand it.” Small concept… big impact 🔥 #Day04 #JavaScript #FrontendDevelopment #LearningDeep #Traversing #Arraybasics

Strengthening Fundamentals: Implementing Selection Sort in JavaScript (Descending Order) Today, I focused on strengthening my understanding of fundamental algorithms by implementing Selection Sort in JavaScript to arrange an array in descending order. Working through the logic step by step provided valuable insight into how sorting algorithms operate internally—particularly the process of identifying elements and performing swaps efficiently without relying on built-in functions. Revisiting these core concepts is a great reminder that a strong foundation in data structures and algorithms is essential for writing optimized and scalable code. You can check out my implementation on my GitHub Looking forward to continuing this learning journey and exploring more advanced problem-solving techniques. #JavaScript #Algorithms #DataStructures #Development #ContinuousLearning #GitHub 😊

Built an efficient LRU Cache from scratch using JavaScript. Key highlights of the implementation: Designed a custom Doubly Linked List for O(1) insertions and deletions Used a HashMap to achieve constant-time access Ensured optimal eviction strategy by always removing the least recently used node Maintained strict O(1) time complexity for both get and put operations Performance: Runtime: 102 ms (faster than ~57% of submissions) Memory: 113.67 MB This problem reinforced how combining data structures (HashMap + DLL) leads to highly optimized systems — a pattern widely used in real-world caching systems like databases and browsers. Continuing to focus on writing clean, efficient, and scalable code. #DataStructures #Algorithms #JavaScript #SystemDesign #Coding

🚀 From Arrays to Efficiency: Mastering Set in JavaScript Today I solved the “Unique Rows in Boolean Matrix” problem using one simple yet powerful concept — Set. At first glance, the problem looks like a typical nested loop challenge. But instead of going brute force, I leveraged Set to achieve a clean and optimal solution. 💡 Key Idea: Convert each row into a string and store it in a Set to automatically handle duplicates. ✨ Why this is powerful: Eliminates duplicates in O(1) lookup time Avoids unnecessary nested loops Keeps the solution clean and readable 📊 Complexity: Time: O(n × m) Space: O(n × m) 🔥 Takeaway: Sometimes, the difference between an average solution and an optimal one is just knowing the right data structure. Today it was Set. Tomorrow, it could be something else. 💬 Curious: Where else have you used Set to simplify a problem? #JavaScript #DSA #CodingInterview #WebDevelopment #ProblemSolving #100DaysOfCode

Most beginners start JavaScript… but don’t understand variables & data types deeply. They declare variables. Store values. Write basic code. It feels easy — until logic gets complex. Then the real problems start: Confusion in data handling. Unexpected bugs. Weak logic building. Difficulty scaling code. In 2026, JavaScript isn’t about syntax. It’s about building strong logic foundations. This is where it starts: • Understanding var, let, const clearly • Knowing different data types (string, number, boolean, object, array) • Storing and managing data efficiently • Writing clean and predictable logic • Avoiding common beginner mistakes Because strong logic doesn’t come from frameworks — it comes from mastering the basics. Curious — are your fundamentals strong or just “working somehow”? #JavaScript #WebDevelopment #Coding #Programming #FrontendDevelopment #LearnToCode #DeveloperLife #JSBasics

💡 Quick JS Trick: Group Anagrams Want to group words that are anagrams of each other? Use sorting & a Map — super clean and efficient: ✅ How it works: 🔹 Sort letters in each word → same letters = same key. 🔹 Use a Map to group words by this key. 🔹 Return all grouped values. ✨ Benefits: ✅ Simple ✅ Fast ✅ Works for any list of strings #JavaScript #CodingTips #Algorithms #DataStructures #CleanCode #WebDevelopment #JSChallenge

🚀 DSA Learning (Realization while solving Top K Frequent Elements) My initial approach was simple: 👉 Count frequency of each number using a HashMap 👉 Then compare frequency with k and push elements into a result array But then I got stuck… ❓ I tried to use .map() directly on the HashMap — and it didn’t work That’s when I realized: - Map is not an array, so array methods like .map() won’t work on it - What actually works: First convert the map into an array 👇 Array.from(map.entries()) Then: ✔️ sort by frequency ✔️ take top k ✔️ extract elements That small shift in understanding made the whole problem click 💡 #DSA #JavaScript #CodingJourney #LeetCode

🚀 Day 9| JavaScript Today I explored JavaScript Foundations: Primitive Data Types & Operations — the building blocks of programming. 📌 Key concepts I learned: 🔹 Primitive Data Types • Number & BigInt → Used for numeric values and large integers • Boolean → Represents true or false (used in decision making) • Null & Undefined → Represent empty or uninitialized values 🔹 Operations in JavaScript • Arithmetic operations (+, -, *, /) • Logical operations (&&, ||, !) • Comparison operations (==, ===, >, <) ⚙️ I also understood how JavaScript performs computational actions to process and manipulate data effectively. 💡 Learning these fundamentals is important to build strong problem-solving skills and write efficient code. Step by step, I’m strengthening my JavaScript basics and programming logic. 💻✨ #JavaScript #WebDevelopment #FrontendDevelopment #CodingJourney #LearningInPublic #DeveloperJourney #ProgrammingBasics