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Leetcode 27: Remove Element Leetcode 27 asks us to remove a specific value from an array. The value to be removed is passed in as a parameter to the function along with the array. Just as we did in Day 1, we will cover a naive approach and an optimized approach and discuss the trade-offs between them. I think in the end there's a pretty clear winner. Let's get started. For both approaches we will use the following values: nums = [1, 3, 3, 2, 4] val = 3 Approach 1: Naive (For Loop + Splice) This approach uses a for loop and leverages .splice() for removals. Solution: var removeElement = function ( nums , val ) { let k = 0 ; for ( let i = 0 ; i < nums . length ; i ++ ) { if ( nums [ i ] === val ) { nums . splice ( i , 1 ); i -- ; } else { k ++ ; } } return k ; }; We begin by initializing a variable k to 0. We then enter the for loop. The condition is standard: create a variable i initialized to 0, continue looping while i is less than nums.length to avoid going past the end of the array, and increment by 1 each time through. Each iteration checks one condition: whether nums[i] is equal to val . If true, we call .splice() on the array. The arguments we pass to splice are i and 1 . i is the index at which we want to start removing, and 1 tells splice to remove only that one element. We then decrement i . The reason for this took me some time to wrap my brain around, so I have included a visual below to make it concrete. The core issue is this: when splice removes an element, every element to the right shifts one index to the left. Without i-- , the loop would increment i on the next iteration and skip right over the element that just shifted in. i-- counteracts that by stepping i back, so after the loop increments it, i lands exactly where the shifted element now sits. If nums[i] !== val , we skip the splice and increment k instead. At the end we return k , which holds the count of elements remaining after all occurrences of val have been removed. Time complexity: O(n²)

I built Xaloia AI , a privacy-first AI platform focused on trust and human interaction. And now, I’m shutting it down. Not because the idea was empty. Not because the tech didn’t work. But because I tried to build it from Romania. The Problem Wasn’t the Product Xaloia was built around things that are becoming increasingly important: privacy secure communication human-centered AI But building something meaningful isn’t enough. It needs the right environment to grow. And that’s where things started to break. What I Ran Into Trying to build in Romania, I kept hitting the same walls: Lack of early adopters willing to pay - People are curious about tech, but not ready to invest in new products. Limited startup ecosystem - Fewer accelerators, fewer investors, fewer people who understand what you’re building. Cultural friction around ambition - If your idea isn’t small or conventional, it’s often questioned instead of supported. Low exposure to global markets - Even if you build something good, getting it in front of the right audience is much harder. None of these stop your project instantly. But together, they slowly drain momentum. Why the US Is Different From everything I’ve seen and experienced, the US offers something fundamentally different: Access to capital — people invest earlier Distribution opportunities — platforms, networks, visibility Cultural support for big ideas — ambition is expected, not questioned Faster feedback loops — you know quickly if something works It’s not that success is guaranteed there. It’s that the conditions for success actually exist. The Real Lesson Talent is everywhere. Ideas are everywhere. But opportunity is not evenly distributed. And trying to ignore that reality cost me time, energy, and a product I genuinely believed in. What’s Next Shutting down Xaloia isn’t the end. It’s a reset—with better clarity. Next time, I won’t just focus on building something good. I’ll focus on building it where it actually has a chance to grow.

Hello Dev Community! 👋 It is officially Day 12 of my journey to master the MERN stack! Today, I wrapped up Lecture 3 of Apna College's JavaScript playlist with Shradha Didi, focusing on a fundamental data type we use every day: Strings . Before today, I thought strings were just plain text wrapped in quotes. Today, I learned how much power JavaScript gives us to manipulate, slice, and dynamically format text. 🧠 Key Learnings From JS Lecture 3 (Strings) I explored how JavaScript handles text strings and the built-in properties and methods that make text manipulation effortless: 1. Template Literals (The Ultimate Game Changer) Shradha Didi introduced Template Literals , which use backticks ( ` ) instead of standard quotes. This allows us to perform String Interpolation —embedding variables directly inside a string using ${variable} . It makes code look clean and professional: javascript let obj = { item: "pen", price: 10 }; // Old way: console.log("The cost of", obj.item, "is", obj.price, "rupees."); // Modern way: console.log(`The cost of ${obj.item} is ${obj.price} rupees.`);

I just joined DEV to explore the community and get into the habit of writing about what I'm learning. I also set up a blog on Hashnode — figuring out how the two fit together. Here's a quick code block to test formatting: ​ function greet ( name ) { console . log ( `Hello, ${ name } !` ); } greet ( " DEV " ); ​ ``` More to come as I find my way around 👋

I Built My First Token on Solana — Here's What Actually Surprised Me This week I went from zero tokens to minting, transferring, charging fees, and locking tokens so they can never move. Here's what stuck with me. Tokens don't live in your wallet Coming from Web2, I assumed tokens would just... show up in your account. Nope. On Solana, every wallet needs a separate token account for each token it holds. One mint, one folder. It felt weird at first. Now it makes sense. You can charge fees without writing a single backend The Token Extensions Program has a built-in transfer fee. One flag at mint creation time: spl-token create-token \ --program-id TokenzQdBNbLqP5VEhdkAS6EPFLC1PHnBqCXEpPxuEb \ --transfer-fee-basis-points 100 That's a 1% fee on every transfer, enforced by the blockchain. No middleware. No payment processor. No way to bypass it. You can make a token that literally cannot be transferred spl-token create-token \ --program-id TokenzQdBNbLqP5VEhdkAS6EPFLC1PHnBqCXEpPxuEb \ --enable-non-transferable I minted 10, tried to send 5, and watched the transaction get rejected. Not by my code — by the program itself. Perfect for credentials, badges, or certificates that should belong to one person forever. The biggest shift from Web2: these rules are set at creation and are permanent. You can't add a transfer fee to an existing token. You can't make a transferable token non-transferable later. It forces you to think about token design upfront, which is honestly a good constraint. solana #blockchain #webdev #beginners #100DaysOfSolana

Hello, I'm Maneshwar. I'm building git-lrc, a Micro AI code reviewer that runs on every commit. It is...

Most AI tutorials start with a setup checklist. Pick a model provider. Create an account. Wire up a...

I recently built Letras Diferentes , a free Unicode text-styling tool for people who want creative copy-paste fonts for bios, nicknames, social posts and gaming profiles. The idea is simple: Type normal text Preview different Unicode styles Copy the result in one click Use it on Instagram, WhatsApp, TikTok, Free Fire, Discord or social posts The project is especially focused on Portuguese-speaking users, but the tool works with general Latin text too. Main project: One thing I’m learning while building it is that Unicode text tools are not just about “fonts”. They are about UX, compatibility, mobile performance, copy buttons, favorites, categories and making the result easy to use on real platforms. I’m still improving the interface, categories and mobile experience. Feedback is welcome.

Web Security Basics Every Developer Must Know (2026) Security isn't just for security teams. Every developer needs these fundamentals to protect their applications and users. The Threat Landscape in 2026 Most common attacks targeting web apps: 1. SQL Injection — Still #1, still devastating 2. XSS (Cross-Site Scripting) — Steals sessions, defaces sites 3. CSRF (Cross-Site Request Forgery) — Actions on behalf of users 4. Authentication bypass — Weak passwords, session fixation 5. Sensitive data exposure — API keys in code, unencrypted data 6. IDOR (Broken Access Control) — Accessing others' data 7. SSRF (Server-Side Request Forgery) — Internal network probing 8. Dependency vulnerabilities — Compromised npm/pip packages Key principle: Defense in depth → Don't rely on one security layer → Multiple independent controls → If one fails, others catch it #1 SQL Injection Prevention // ❌ VULNERABLE: String concatenation const query = `SELECT * FROM users WHERE email = ' ${ email } '` ; // Attacker inputs: ' OR '1'='1' -- // Result: Returns ALL users! // ✅ Parameterized queries (always!) const user = db . prepare ( ' SELECT * FROM users WHERE email = ? ' ). get ( email ); // The database treats the input as DATA, not code. // With ORM (Sequelize/TypeORM/Prisma): User . findOne ({ where : { email } }); // Safe by default // Even with parameterized queries, validate input first: function isValidEmail ( email ) { return /^ [^\s @ ] +@ [^\s @ ] + \.[^\s @ ] +$/ . test ( email ); } if ( ! isValidEmail ( email )) return res . status ( 400 ). json ({ error : ' Invalid email ' }); // ⚠️ Dangerous: Dynamic table/column names can't be parameterized! const allowedTables = [ ' users ' , ' products ' , ' orders ' ]; if ( ! allowedTables . includes ( table )) throw new Error ( ' Invalid table ' ); #2 XSS (Cross-Site Scripting) Defense // Types of XSS: // 1. Stored XSS: Malicious script saved in DB, shown to all viewers // → Comment sections, profiles, product reviews // 2. Reflected XSS: Sc

Introduction Since I started publishing articles on Dev.to, I've been working on a personal project to transform my old blog website—which is no longer actively maintained—into a portfolio site ♻️ As part of that project, I recently started learning Figma and UI design🎨 When I discovered Figma MCP , I imagined a future where generative AI could automatically create polished, modern, and visually appealing designs for me with minimal effort 😎 Unfortunately, reality turned out to be quite different . This article is a reflection on that experience and a reminder to my future self about what I learned along the way📝 TL;DR I wanted to design a portfolio website in Figma , but quickly realized that UI design was more difficult than I expected. I wondered whether using Codex and Figma MCP would allow me to outsource the design process to AI , so I decided to try it. I couldn't magically generate the polished design I had imagined while also maintaining a well-structured Figma file with globally managed variants and reusable components. I learned that defining design rules first and building components step by step helped produce results that were much closer to my original vision. Even then, the process was not dramatically easier than expected, so I eventually decided to keep things simple and build my portfolio around the design principles already provided by shadcn/ui . What I Tried with Figma MCP🎨 While planning the UI design for my portfolio website , I initially created simple wireframe-like layouts in Figma to explore the overall page structure and component placement before working on detailed designs. At first, I wanted to keep things simple. However, as I continued working on the project, I found myself wanting something more polished, more modern, and ultimately more impressive . The problem was that I have very little confidence in my design skills. I'm an in-house IT engineer, not a professional developer or designer, so I often struggle to judge what makes a

Here's a conversation I've had more than once. A developer is building a React app. It starts...

We've all been there. You're 45 minutes into a Docker tutorial, feeling great about yourself, and then someone casually drops: "Just pull the image and spin up a container." And you think: "...wait, aren't those the same thing?" First - this has happened to a good number of us if we are to be honest. Even almost every single DevOps engineer, cloud architect, and platform wizard you admire has typed the wrong term in a sentence at least once in their career. It's practically a rite of initiation. There should be a badge for it if you ask me. Why Does This Trip Everyone Up? Here's the sneaky truth: Docker commands blur the line constantly. You type docker run nginx and something called a "container" starts — but wait, didn't you just use an "image" called nginx ? Where did one end and the other begin? The confusion lives in the fact that they are deeply related — one literally gives birth to the other. But they are fundamentally, completely different things. Getting this distinction straight is your official rite of passage into DevOps. Once it clicks, the rest of Docker feels like cheating. Basically, A Docker Image is the blueprint : a frozen, static snapshot of everything your app needs - the OS layer, the dependencies, the config files, your actual code. It just sits there on disk, completely inert. You can't run a blueprint. A Docker Container is the house : the live, running instance that was built from that blueprint. It has processes running, files potentially being written, network ports being listened on. It's alive. And now, just like one blueprint can produce 10 identical houses on different streets - one Image can launch 10 identical Containers simultaneously; and that's where Docker's scaling magic comes from. # The image just sits here, unchanging docker pull nginx # Now we BUILD a house (container) from the blueprint docker run nginx # Build THREE houses from the same single blueprint docker run nginx docker run nginx docker run nginx Here is an exampl

There is a special kind of productivity theater that happens during a developer job search. You wake up motivated, open LinkedIn, and apply to 27 positions before breakfast. You press the Easy Apply button with the precision of a professional gamer. By the end of the week, you have submitted 143 applications, updated a spreadsheet with several impressive numbers, and developed a minor emotional dependency on refreshing your inbox. Unfortunately, your inbox still looks like an abandoned shopping mall. No interviews. No useful feedback. No clear explanation. Perhaps two automated emails thanking you for your interest before informing you that the company decided to “move forward with other candidates,” a sentence that has become the corporate version of disappearing into the fog. So you decide to solve the problem by applying to another 200 jobs. This is not a strategy. It is email-based agriculture. You are throwing resumes into the soil and waiting for a recruiter to grow. Volume Matters. Blind Volume Does Not. Let us begin with an uncomfortable truth: getting your first developer job usually requires applications. Sometimes it requires many applications. The market will not discover your GitHub profile through divine intervention. A recruiter is unlikely to wake up in the middle of the night with a mysterious urge to search for junior developers who recently deployed a to-do list. You need to put yourself in front of companies consistently. However, there is a significant difference between applying consistently while improving your positioning and clicking every blue button on LinkedIn until one of you collapses. Volume is useful when it generates information. Blind volume only produces exhaustion. If you apply to 300 jobs with the same generic resume, the same generic portfolio, and the same vague explanation of your skills, you are not running 300 experiments. You are repeating the same experiment 300 times and acting surprised when the result remains unchanged.

Hello Dev Community! 👋 It is officially Day 8 of my journey to master the MERN stack! After spending the first week structuring with HTML and styling with CSS, today I finally started learning the core language of web logic: JavaScript . Moving from static designs to actual programming logic feels like unlocking a whole new level of web development. 🧠 Key Learnings From Day 8 Today was all about setting up the foundation in JavaScript and understanding how code runs in the browser. Here is what I covered: 1. The Browser Console & Execution I learned that every browser has a built-in environment to run JavaScript. Writing my very first console.log("Hello World"); and seeing it print in the developer tools console was the perfect start. 2. Variables: Storing Data Safely I learned how to store information using variables and the crucial differences between modern variable declarations: let : For values that can change later in the program (mutable). const : For values that must remain constant and cannot be reassigned (immutable). Note: I also read about var , but learned why modern JavaScript avoids it due to scoping issues. 3. Data Types Fundamentals Data needs a type so the computer knows how to handle it. Today I practiced with: Strings: Plain text enclosed in quotes (e.g., "MERN Stack" ). Numbers: Integers and decimals without quotes (e.g., 2026 ). Booleans: Simple true or false states (e.g., isLearning = true ). 🛠️ What I Actually Code / Experimented With Since I am just starting with core logic, I didn't write code directly into my HTML webpage layout today. Instead, I created a script.js file, linked it to my project, and built a basic script in the console that: Stores a user's name and learning status in variables. Dynamically calculates values (like years left until a milestone). Outputs formatted statements into the browser console. It is simple, but understanding how data moves in the background is incredibly exciting. 🎯 My Goal for Tomorrow (Day 9) Tomorr

Tuples, Sets, and Dictionaries in Python In the previous lesson, we learned about Lists and how they are used to store multiple items in a single variable. Today, we will learn about three important Python data structures: Tuples Sets Dictionaries These data structures help programmers organize and manage data efficiently in different situations. 1. Tuples in Python A Tuple is a collection of items stored in a single variable. Tuples are: Ordered Unchangeable (Immutable) Allow duplicate values Tuples are created using parentheses "()". Example languages = ( " Python " , " Java " , " C++ " ) print ( languages ) Output ( ' Python ' , ' Java ' , ' C++ ' ) Accessing Tuple Items Tuple items are accessed using indexes. Example languages = ( " Python " , " Java " , " C++ " ) print ( languages [ 0 ]) print ( languages [ 1 ]) Output Python Java Negative Indexing in Tuples Example languages = ( " Python " , " Java " , " C++ " ) print ( languages [ - 1 ]) Output C ++ Tuple Length The "len()" function returns the number of items in a tuple. Example numbers = ( 10 , 20 , 30 ) print ( len ( numbers )) Output 3 Why Tuples are Important Tuples are useful when data should not be modified accidentally. They are commonly used for: Fixed data Coordinates Database records Returning multiple values from functions 2. Sets in Python A Set is a collection of unique items. Sets are: Unordered Unchangeable items Do not allow duplicates Sets are created using curly brackets "{}". Example numbers = { 1 , 2 , 3 , 4 } print ( numbers ) Output {1, 2, 3, 4} Duplicate Values in Sets Sets automatically remove duplicate values. Example numbers = { 1 , 2 , 2 , 3 , 4 } print ( numbers ) Output {1, 2, 3, 4} Adding Items to a Set The "add()" method inserts a new item into a set. Example numbers = { 1 , 2 , 3 } numbers . add ( 4 ) print ( numbers ) Output {1, 2, 3, 4} Removing Items from a Set The "remove()" method removes an item from a set. Example numbers = { 1 , 2 , 3 , 4 } numbers . remove ( 2 ) print

Introduction Understanding how to find prime numbers is one of the best ways to develop logical thinking in programming. It looks simple on the surface, but it teaches you how to break a problem into smaller steps, build a solution gradually, and then improve it into a clean and reusable structure. In this blog, we will not jump directly into code. Instead, we will start from basic thinking, slowly convert that thinking into logic, and finally refine it into a proper Python program using functions and loops. The goal is not just to find prime numbers, but to understand how programming logic is actually built in real development. 1. Understanding the Problem First Before writing anything in Python, we need to understand what a prime number actually means. A prime number is a number that: is greater than 1 has exactly two divisors: 1 and itself So the real question becomes: How do we check whether a number has any divisors other than 1 and itself? That is the core problem we are trying to solve. 2. Thinking Like a Human Before Coding Let’s take a number, for example 13. To check if 13 is prime, we naturally try dividing it by smaller numbers: 2 → does not divide 13 3 → does not divide 13 4 → does not divide 13 5 → does not divide 13 and so on If none of these numbers divide 13 completely, then 13 is prime. So the logic is simple: Try dividing the number by possible candidates and see if any divide it perfectly. 3. Turning Thinking into a Basic Algorithm From the above idea, we can form a basic structure: We need: a number to test a variable that moves through possible divisors a way to detect whether a divisor exists We start checking from 2 because every number is divisible by 1 anyway. We also do not need to check beyond half of the number, because a number cannot have a divisor greater than half (except itself). So the idea becomes: Start divisor from 2 Go up to number // 2 If any number divides it evenly, it is not prime 4. First Working Logic (Direct Implementati

In May, I continued my "One Commit a Day" Challenge and spent more time contributing across different open-source projects. Compared to April, I was able to contribute a bit more and explore a wider variety of repositories. Repositories That Stood Out Some of the projects that left the biggest impression on me were: python-odpt Huggin Face Context Course Human Signal ML ScribeSVG A Stable Checkpoint One milestone I was happy about this month was reaching a stable checkpoint for my Tokyo MCP Server project. It is still a work in progress, but getting to a point where the project feels stable enough to build upon was a satisfying moment. Documentation Matters Another contribution that stood out was helping improve a python-odpt README documentation . It wasn't a large technical contribution, but it reminded me that making a project easier for others to understand can be just as valuable as writing code. Good documentation lowers the barrier for future contributors. Sometimes, a clearer README can help more people than a small code change. Learning Beyond Python One practical lesson I learned this month was that being a Python-focused contributor doesn't mean I can ignore the JavaScript ecosystem . While working with different repositories, I finally installed Node.js and started using npm . Many modern open-source projects rely on TypeScript-based tooling, build systems, or development workflows, and understanding those tools makes contributing much easier. The Biggest Challenge: Finding Information And Communication Matters The biggest challenge I faced wasn't coding. It was documentation. Every repository has its own way of organizing information. There are definitely common patterns, but every project also develops its own style over time. Sometimes the information I need is in the README. Sometimes it's in a wiki. Sometimes it's buried in a docs folder several levels deep. And sometimes it's spread across all three. Open Source Is Also About Navigation As a contri

Every time I sit down to learn something, I find myself trapped in the same cycle. I start with a tutorial. Halfway through, someone says there's a better tutorial. I switch. Then I discover a book that supposedly explains the topic better than the tutorial. Then a YouTube video claims the book is outdated. Then a developer on social media recommends an entirely different resource. Before I know it, I've spent three hours researching how to learn instead of actually learning. Does the information overload stop or will there always be another resource, another course, another book, another video, another roadmap, another expert with a different opinion. The internet has made knowledge abundant, but abundance creates a paradox of choice. One person says to learn JavaScript from documentation, another says build projects immediately, another recommends a paid course, someone else insists that free resources are better. Every recommendation sounds convincing. Every path seems important. The result is paralysis. Instead of moving forward, I keep searching, instead of building I keep comparing, instead of learning I keep consuming. finished teaches more than a hundred bookmarked tutorials. At some point, every learner must accept a difficult truth that the goal is not to find the best resource it is to become better. Those are not the same thing. A person can spend months researching the perfect learning path and never write a meaningful line of code while another person can pick a decent resource, make mistakes, build projects, and improve every day. The second person wins not because they found better information but because they used the information they already had. I've started realizing that learning is a lot like fitness. At some point, reading about exercise becomes a form of avoiding exercise. The same thing happens in programming. Reading about coding becomes a way to avoid coding. Researching becomes a substitute for practice. The search for the perfect resourc

If you've ever worked with auth, you've seen a JWT — a long string like eyJhbGci... split into three parts by dots. It looks cryptic, but it's surprisingly simple once you see inside. A JWT has three parts header.payload.signature Header – tells you the signing algorithm, e.g. {"alg":"HS256","typ":"JWT"} Payload – the claims (the actual data), e.g. {"sub":"123","name":"John","iat":1516239022} Signature – verifies the token wasn't tampered with (needs the secret/key) The header and payload are just Base64url-encoded JSON — not encrypted. That means anyone can read them. So: ⚠️ Never put secrets in a JWT payload. It's signed, not hidden. Decoding one yourself You can decode the payload in the browser console: const [, payload ] = token . split ( " . " ); console . log ( JSON . parse ( atob ( payload ))); Or, if you just want to paste a token and instantly see the header + payload (without sending it to a server), I built a free decoder that runs entirely in your browser: https://forgly.dev/tools/jwt-decoder Decoding ≠ verifying Reading a JWT is trivial. Trusting it is not — you must verify the signature on your server with the secret/public key before relying on any claim. Decoding just lets you inspect what's there. That's the whole mental model: a JWT is a readable, signed envelope — not a locked box.

As part of my game development journey, I recently created Hidden Collector , a Unity-based game where players explore levels and collect hidden items while progressing through different challenges. This project started as a way for me to improve my Unity and C# skills, but it quickly became an opportunity to learn about game design, UI systems, audio management, scene transitions, and player experience. What I Worked On While building Hidden Collector, I implemented: Player movement and interactions Collectible item systems Multiple game levels UI menus and game screens Audio and sound effects Progress tracking Game flow and scene management Challenges During Development One of the biggest challenges was making different game systems work together smoothly. Something as simple as collecting an item often required updates to UI elements, game state management, and progression systems. Debugging these interactions taught me a lot about organizing Unity projects and writing maintainable code. What I Learned This project helped me gain experience with: Unity Engine C# scripting Game architecture UI implementation Audio management Debugging and testing Most importantly, I learned that building complete projects teaches far more than following tutorials. Play the Game You can try Hidden Collector here: https://sinxcos07.itch.io/hiddencollector Screenshots What's Next? I'm continuing to improve my game development skills by building new projects, experimenting with different mechanics, and learning more about creating engaging player experiences. If you try the game, I'd love to hear your feedback. By Suryansh Sinha (sinxcos07) Connect With Me GitHub: https://github.com/sinxcos07 LinkedIn: https://www.linkedin.com/in/suryansh-sinha/ Play Hidden Collector: https://sinxcos07.itch.io/hiddencollector