Reversing Strings and Numbers in JavaScript with Functions

🚀 Day 4 of my JavaScript Coding Practice Today’s problem: Two Sum var twoSum = function(nums, target) { const map = new Map(); // Store: { value : index } for (let i = 0; i < nums.length; i++) { const complement = target - nums[i]; // If the needed number is already in our map, we found the pair! if (map.has(complement)) { return [map.get(complement), i]; } // Otherwise, save the current number and its index map.set(nums[i], i); } return []; // Return empty if no pair is found }; 💡 Instead of using brute force (O(n²)), I used a HashMap approach to solve it in O(n) time. Key takeaway: Understanding how to trade space for time can significantly optimize performance. Small steps every day → Big improvements over time 📈 #JavaScript #DSA #CodingPractice #100DaysOfCode #FrontendDevelopment

Mastering Callbacks in JavaScript – The Foundation of Async Programming If you're learning JavaScript, understanding callbacks is a game-changer. 💡 Functions in JS are first-class citizens — meaning you can pass them around just like data. 👉 That’s where callbacks come in. From simple synchronous execution to real-world async scenarios like timers, events, and API calls — callbacks power it all. But there’s a twist… 😵💫 As your logic grows, you may hit the infamous Callback Hell (Pyramid of Doom) — deeply nested, hard-to-read code. ⚠️ Why it happens: • Each async task depends on the previous one • Callbacks keep stacking • Readability takes a hit ✅ Modern solutions: • Promises • Async/Await These make your code cleaner, more readable, and easier to maintain. 📌 Key takeaway: Callbacks are not outdated — they are the foundation. Master them, and everything else (Promises, Async/Await) becomes easier. #JavaScript #WebDevelopment #Frontend #AsyncProgramming #Coding #100DaysOfCode #DevTips #LearnToCode #chaicode Chai Aur Code

🚀 Diving into JavaScript Functions! 🚀 Functions are like recipes in programming 🍳 They are blocks of code that perform a specific task when called. Developers use functions to organize code, make it reusable, and improve readability. Understanding functions is essential for every developer to write efficient and maintainable code. Let's break it down: 1️⃣ Declare a function using the keyword "function" followed by a name and parameters. 2️⃣ Write the code block inside curly braces to define what the function does. 3️⃣ Call the function by using its name and passing any required arguments. Check out this example: ```javascript function greet(name) { return `Hello, ${name}!`; } console.log(greet("Alice")); ``` Pro Tip: Don't forget to use meaningful function names and keep them concise for better code organization. 🌟 Common Mistake Alert: Forgetting to return a value from the function can lead to unexpected behavior. Always ensure your functions explicitly return a value when needed. 🤔 What's your favorite function to write and why? Share in the comments below! 🤓 🌐 View my full portfolio and more dev resources at tharindunipun.lk #JavaScriptFunctions #CodeOrganization #ReusableCode #WebDevelopment #LearnToCode #ProgrammingTips #FunctionBestPractices #TechTutorials #DeveloperCommunity

Understanding JavaScript arrays changed how I think as a developer. Coming from a teaching background I thought coding was memorizing syntax. Feeling a level of guilt when I pulled out my cheat sheet. But working with arrays like .map( ) and .reduce( ) helped me make a lasting connection. It’s not about memorizing code. It’s about solving problems efficiently. Instead of looping manually, I can transform and analyze data in a much cleaner way. If you’re learning JavaScript, stick with it until it clicks! Now I focus less on memorizing and more on understanding patterns. #SoftwareDeveloper #Tech #FullStack #JavaScript #SoftwareEngineer #WebDevelopment #MERNStack

Day 07 of My JavaScript Learning 👉 Finding the largest among three numbers How to compare multiple values using if-else Writing clean and readable conditions Converting logic into a reusable function // Find the largest among 3 numbers let firstNum = 5; let secondNum = 10; let thirdNum = 2; if (firstNum >= secondNum && firstNum >= thirdNum) { console.log(firstNum); } else if (secondNum >= firstNum && secondNum >= thirdNum) { console.log(secondNum); } else { console.log(thirdNum); } 🔁 Making it reusable with a function: let largestInFunction = function(firstNum, secondNum, thirdNum) { if (firstNum >= secondNum && firstNum >= thirdNum) { return firstNum; } else if (secondNum >= firstNum && secondNum >= thirdNum) { return secondNum; } else { return thirdNum; } } console.log(largestInFunction(3, 1, 4)); 🌱 My takeaway: Even simple problems help build strong fundamentals. The goal is not just solving — but understanding the logic behind it. #Day07 #JavaScript #LearningJourney #FrontendDeveloper #CodingPractice

🚀 Day 7 / 30 - JavaScript Coding Practice Today’s challenge: Recreating the Array.map() functionality — without actually using it 👀 Problem: Apply a transformation function to each element of an array and return a new array. 💡 Key Insight: This problem helped me understand what’s happening under the hood of built-in methods like map(). 👉 Instead of relying on .map(), I used a loop to: Iterate through each element Apply the given function with both value & index Build a new transformed array Solution: var map = function (arr, fn) {     let transArr = []     arr.forEach((element, i) => {         transArr.push(fn(element, i) ?? element);     });     return transArr; }; #JavaScript #DSA #CodingPractice #100DaysOfCode #FrontendDevelopment #ProblemSolving

I recently started diving deeper into JavaScript, and honestly… one concept completely changed how I see code execution 🤯 At first, I used to just write code and expect it to “run.” But then I discovered what actually happens behind the scenes 👇 JavaScript doesn’t just execute code directly. It goes through a process: 🔹 First, it creates a Global Execution Context 🔹 Then comes the Memory Phase (where variables get stored as undefined and functions are fully saved) 🔹 After that, the Execution Phase runs code line by line 🔹 And everything is managed using a Call Stack (LIFO — Last In, First Out) Understanding this made things like hoisting, function calls, and even bugs feel way less random. Now when I write code, I don’t just see syntax — I can actually visualize what the JavaScript engine is doing step by step 🧠⚡ Still learning, but this was one of those “aha” moments that made everything clearer. If you're learning JavaScript, don’t skip this part — it’s a game changer 🚀 #JavaScript #WebDevelopment #LearningJourney #Frontend #Programming #Developers

Building Subsets on Day 226 Today Today is day 226 of my coding journey and I focused on solving the Power Set problem using JavaScript. This involves finding every possible combination of elements from a given array including the empty set. I used the Backtracking technique to explore all paths. The logic starts with an empty array and then adds elements one by one. After exploring a specific path I used the pop method to remove the last element. This is the unchoose step that allows the code to go back and try a different number. One important thing I practiced today is how to use the spread operator to create a copy of the current path before adding it to the result. This ensures that the final list contains the correct values instead of just references to an empty array. Understanding how recursion builds a state space tree makes solving these types of problems much clearer. I solved this LeetCode question today: LeetCode 78 Subsets #DSAinJavaScript #365daysOfCoding #JavaScriptLogic #LeetCode #BacktrackingAlgorithms #Recursion #ProblemSolving #CodingChallenge #WebDevelopment #SoftwareEngineering #DataStructures #LogicBuilding #TechLearning #JSAlgorithms #SoftwareDevelopment #CodingSkills #DailyCoding #ArrayManipulation #FullStackDeveloper #ProgrammingJourney

Day 13 of My JavaScript Journey 🚀 Today’s lesson was different and very important. I learned how to effectively use tools like Google and Stack Overflow to solve problems, and I was introduced to debugging. Debugging is the process of identifying and fixing errors (bugs) in code. The process can be summarized as: • Find the problem • Fix the issue • Prevent it from happening again I also learned that bugs are a normal part of programming every developer deals with them. One key insight: Being a good developer is not about knowing everything, but about knowing how to find solutions. Key takeaway: Problem-solving and debugging are core skills in programming. I’m documenting my journey daily as I grow in JavaScript. #JavaScript #WebDevelopment #LearningInPublic #100DaysOfCode

🚀 Day 15 of #100DaysOfCode Today was all about mastering two powerful JavaScript concepts that make code cleaner, smarter, and more expressive: 👉 Array Destructuring 👉 Spread Operator 💡 1. Array Destructuring No more messy indexing! You can unpack values from arrays in a clean way: const arr = [10, 20, 30]; const [a, b, c] = arr; console.log(a, b, c); // 10 20 30 You can even skip values or set defaults: const [x, , z = 50] = [5, 15]; console.log(x, z); // 5 50 ⚡ Cleaner code = better readability. 💡 2. Spread Operator (...) This tiny syntax unlocks big power 💥 👉 Copy arrays: const arr1 = [1, 2, 3]; const arr2 = [...arr1]; 👉 Merge arrays: const a = [1, 2]; const b = [3, 4]; const merged = [...a, ...b]; 👉 Add elements easily: const nums = [1, 2, 3]; const updated = [...nums, 4]; 🔥 No loops. No push chaos. Just elegance. ✨ Key Takeaway: Destructuring simplifies access. Spread operator simplifies manipulation. Together? They make your JavaScript feel like magic 🪄 📈 Consistency is the real superpower. Showing up every day. Learning every day. #JavaScript #WebDevelopment #CodingJourney #100DaysOfCode #LearnInPublic #Developers #LearningInPublic Sheryians Coding School Sheryians Coding School Community