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Roman to Integer Conversion Flow

This document explains the romanToInt function, which converts a Roman numeral string to its integer equivalent. The function is implemented in JavaScript and handles standard Roman numeral rules, including subtractive cases (e.g., IV = 4). Below, we provide a Mermaid flowchart to visualize the algorithm's flow and a step-by-step example for the input "XIV".

Function Overview

The romanToInt function takes a string s of Roman numerals and returns the corresponding integer. It uses a dictionary to map Roman symbols to their values and processes the string from left to right, handling subtractive cases by checking if the next symbol has a greater value.

Code

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Diagrams for "MCMXCIV"

This document illustrates the execution of three solutions for the "Roman to Integer" problem (LeetCode 13) using the valid Roman numeral string "MCMXCIV" (1994). The solutions are:

• First Pass: Naive addition of each symbol’s value.
• Second Pass: Compare adjacent symbols to handle subtractive cases.
• Final Solution: Single-pass addition with correction for subtractive cases.

Each solution is visualized with a Mermaid sequence diagram showing the step-by-step processing of "MCMXCIV". A flowchart for the Final Solution’s logic is also included, with notes on how it differs for the other solutions.

Flowchart: Algorithm Logic (Final Solution)

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Understanding For Loops in JavaScript

A for loop in JavaScript is a way to repeat a block of code a specific number of times or until a condition is met. It’s commonly used when you know how many times you want to run the loop or need to iterate over a sequence, like numbers, elements in an array, or characters in a string. This guide breaks down the for loop into its simplest parts, focusing on the syntax like (let i = 0; i < someValue; i++), with examples to make it clear for beginners.

What is a For Loop?

A for loop runs a block of code repeatedly based on a condition. It’s structured to initialize a counter, check a condition, and update the counter after each iteration. Here’s the basic syntax:

for (initialization; condition; update) {
 // Code to execute in each iteration

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URL Shortener Diagrams

This markdown file contains various diagrams illustrating the system design, flows, and architecture of the URL Shortener microservice. All diagrams are rendered using Mermaid syntax for easy visualization in compatible viewers (e.g., GitHub, Markdown editors with Mermaid support).

1. High-Level Architecture Diagram

This flowchart shows the overall system components and their interactions.

graph TD
 A[Client/User] -->|"POST /api/shorten"| B[API Gateway/Controller]

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URL Shortener Task List

This markdown file outlines a detailed task list for building the URL Shortener project from initial creation to production deployment. The structure is organized into Pull Requests (PRs) as high-level milestones, each containing Epics (feature groups), and each Epic broken down into Commits (granular, atomic tasks). Each task is presented as a TODO checkbox for easy tracking.

This is designed for a solo developer or team using Git for version control. Assume you're working on a main branch, with feature branches for each Epic (e.g., feature/project-setup). Commits should be small and focused, with descriptive messages. After completing an Epic, create a PR to merge into main.

Use tools like GitHub Issues or a simple TODO app to track progress. Estimated times are rough (assuming 4-8 hours/day for a novice).

PR 1: Initial Setup and Core Structure

This PR focuses on bootstrapping the project, setting up the environment, and basic architecture. Goal: A runnable

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URL Shortener PRD

Synopsis

This Product Requirements Document (PRD) outlines the requirements for building a URL Shortener microservice. The application allows users to shorten long URLs into compact, shareable links, redirect to the original URL when accessed, and track basic analytics like click counts. Designed as a backend-focused project using Java Spring Boot, it serves as a portfolio piece. The goal is to create a simple, deployable API that demonstrates core backend skills, with instructions clear enough for a novice developer, LLM, or AI assistant to implement from scratch to production.

Executive Summary

The URL Shortener is a lightweight web service inspired by tools like Bitly or TinyURL. It provides RESTful endpoints for creating short URLs, redirecting to originals, and viewing analytics. Key benefits include ease of implementation, scalability potential, and relevance in real-world applications (e.g., marketing, social media). Target users are developers testing APIs or end-users need

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🚀 Backend Java Developer Portfolio Projects

This document lists 10 potential portfolio projects designed to showcase backend Java development skills, including Spring Boot APIs, SQL/NoSQL databases, desktop applications, and Docker.

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1. Task Manager API

• Category: Spring Boot REST API
• Core Features: CRUD for tasks, user authentication, JWT, PostgreSQL persistence
• Skills Showcased: Spring Boot API design, SQL (Postgres), Dockerized local development

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LangGraph Advice for HTML-to-React Project

Why LangGraph > Prompts

• Modularity: Break your task into nodes (e.g., parse HTML, identify components, generate React code). Update one node for changes, not the whole prompt.
• State Tracking: Persist data (like parsed HTML) across nodes, avoiding repetitive context in prompts.
• Control Flow: Use conditional edges or loops to handle varied HTML structures, unlike linear prompts.
• Debugging: Inspect each node’s output with tools like LangSmith, easier than opaque prompt failures.
• Tool Integration: Add libraries (e.g., BeautifulSoup) or APIs (e.g., code validation) for robust workflows.

Getting Started

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scanf_s Family Functions Reference

Overview

The scanf_s family are secure versions of the standard scanf functions with enhanced security features to prevent buffer overruns. This guide focuses on sscanf_s and swscanf_s for parsing strings.

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Function Variants

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Windows API Time Structures Reference

Overview

Windows API provides two main structures for handling date and time: FILETIME and SYSTEMTIME. Each serves different purposes in time representation and manipulation.

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FILETIME Structure