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Debugging a Password Program with x64dbg

This guide outlines the steps to build and debug a simple C password-checking program using GCC in MSYS2 and x64dbg on Windows. The goal is to compile the program with specific flags, load it into x64dbg, set a breakpoint on strcmp, analyze function parameters, identify the correct password, and verify it. Mermaid diagrams are included to visualize the compilation and debugging processes.

Program Code

The C program (password.c) to debug is:

#include <stdio.h>
#include <string.h>

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Introduction to COBOL Programming with GnuCOBOL

Course Overview

This course provides a comprehensive introduction to COBOL programming using GnuCOBOL, an open-source COBOL compiler. Designed for beginners and intermediate programmers, the course covers fundamental programming concepts, data structures, practical applications, and advanced topics such as database integration. Each module builds on the previous one, ensuring a structured learning path that equips students with the skills to write robust COBOL programs for business applications.

Course Objectives

• Understand COBOL syntax and structure using GnuCOBOL.
• Master core programming concepts like variables, conditionals, and iteration.
• Implement data structures and basic algorithms in COBOL.

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Step-by-Step Execution of Iterative joinAll for [ ["x", "y"], ["z"] ]

This document walks through the execution of the non-recursive iterative joinAll function for the input [ ["x", "y"], ["z"] ], which generates all possible permutations of strings from the input lists, joined by underscores. The function produces ["x_z", "y_z"]. Each step of the iterative process is detailed below, with a Mermaid diagram visualizing the state of the algorithm, including the result and new_result lists. The diagrams are compatible with GitHub’s Mermaid renderer.

Iterative joinAll Implementation

The iterative solution builds combinations by maintaining a list of partial combinations (result) and updating it for each sublist.

def joinAll(lls):

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Walkthrough: Solving the joinAll Problem for Lists of Permutations

This walkthrough is designed to help you guide students through solving the joinAll problem, which involves generating all possible permutations of strings from a list of lists, joined by underscores. The goal is to provide a clear path to the solution while fostering understanding of key concepts like recursion, iteration, and Cartesian products. Below, we break down the problem, offer hints, suggest teaching strategies, provide a step-by-step solution approach, and include Mermaid diagrams to visualize the process, ensuring compatibility with GitHub's Mermaid renderer.

Problem Recap

The joinAll(lls) function takes a list of lists of strings and returns a list of all possible permutations, where each permutation is formed by selecting exactly one string from each sublist and joining them with underscores (_).

Example

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Problem Set: Lists of Permutations

Problem Description

You are tasked with writing a function joinAll(lls) which takes in a list of lists of strings and returns every permutation of elements from those lists, joined together with underscores (_).

Requirements:

1. The input is a list of lists of strings (e.g., [ ["a","b"], ["c"], ["d","e"] ]).
2. Each output string should be formed by picking exactly one element from each list in order, then joining them with underscores.

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🛡️ Network Security Learning Path (Zero → High-Paid Expert)

This roadmap combines structured curriculum (week-by-week) and milestone checkpoints so you can track progress whether you study part-time or full-time.

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📚 Phase 0: Foundations (6–9 months | ~500 hrs)

Goal: Build computer, networking, and programming basics.

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Building a Simple HTTP Server in Java: Problem Set

Introduction

This problem set guides you through building a basic HTTP server from scratch using Java's standard library, specifically the java.net.ServerSocket and java.net.Socket classes. The goal is to create a server that handles simple GET requests, parses incoming HTTP requests, and sends valid HTTP responses. We'll break it down into "tickets" – small, incremental tasks that build upon each other, simulating a real-world project workflow.

Prerequisites:

• Basic Java knowledge (sockets, I/O streams, file handling, string manipulation).
• No external libraries are allowed; use only Java's standard library (e.g., java.net, java.io, java.nio.file).
• Test your server using tools like curl (e.g., curl http://localhost:8080/) or a web browser.

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Building a Simple HTTP Server in JavaScript: Problem Set

Introduction

This problem set guides you through building a basic HTTP server from scratch using Node.js's http module. The goal is to create a server that handles simple GET requests, parses incoming HTTP requests, and sends valid HTTP responses. We'll break it down into "tickets" – small, incremental tasks that build upon each other, simulating a real-world project workflow.

Prerequisites:

• Basic JavaScript knowledge (Node.js, objects, file system operations).
• No external libraries are allowed; use Node.js's built-in modules (e.g., http, fs, url).
• Test your server using tools like curl (e.g., curl http://localhost:8080/) or a web browser.

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Building a Simple HTTP Server in Python: Problem Set

Introduction

This problem set guides you through building a basic HTTP server from scratch using Python's standard library (primarily the socket module). The goal is to create a server that can handle simple GET requests, parse incoming HTTP requests, and send valid HTTP responses. We'll break it down into "tickets" – small, incremental tasks that build upon each other, simulating a real-world project workflow.

Prerequisites:

• Basic Python knowledge (sockets, strings, file I/O).
• No external libraries are allowed; stick to Python's built-in modules.
• Test your server using tools like curl (e.g., curl http://localhost:8080/) or a web browser.

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AWS Deployment Guide

Assuming you have an AWS IAM console login with admin privileges (which gives you full access to create resources). We'll deploy your Next.js 14 app (with API routes as backend) using AWS Amplify for hosting the frontend and backend, and AWS RDS for a PostgreSQL database (replacing Supabase). AWS Amplify is beginner-friendly as it handles deployment, CI/CD, and scaling automatically.

Important Notes Before Starting:

• This assumes your app is in a Git repository (e.g., GitHub). If not, push it to GitHub first.
• We'll use the AWS Management Console (web interface) for all steps—no CLI needed.
• Costs: AWS has a free tier, but RDS and Amplify may incur small charges (e.g., ~$0.025/hour for a basic RDS instance). Monitor via AWS Cost Explorer.
• Security: Use environment variables for secrets (e.g., DB connection strings, API keys). Avoid hardcoding them.
• Time Estimate: 1-2 hours for setup, plus deployment time.