Skerritt.blog

programming

Divide and Conquer Algorithms with Python Examples

Often I’ll hear about how you can optimise a for loop to be faster or how switch statements are faster than if statements. Most computers have over 1 core, with the ability to support multiple threads. Before worrying about optimising for loops or if statements try to attack your

programming

Ripgrep cheatsheet

I use RipGrep all the time, but sometimes when I want to do something I have to search the internet to find out. GitHub - BurntSushi/ripgrep: ripgrep recursively searches directories for a regex pattern while respecting your gitignoreripgrep recursively searches directories for a regex pattern while respecting your gitignore

Algorithms Featured

All You Need to Know About Big O Notation [Python Examples]

By the end of this article, you’ll thoroughly understand Big O notation. You’ll also know how to use it in the real world, and even the mathematics behind it! In computer science, time complexity is the computational complexity that describes the amount of time it takes to run

Popular Featured

Timsort — the fastest sorting algorithm you’ve never heard of

Timsort: A very fast , O(n log n), stable sorting algorithm built for the real world — not constructed in academia. Timsort is a sorting algorithm that is efficient for real-world data and not created in an academic laboratory. Tim Peters created Timsort for the Python programming language in 2001. Timsort

Algorithms

Greedy Algorithms In Python

Greedy algorithms aim to make the optimal choice at that given moment. Each step it chooses the optimal choice, without knowing the future. It attempts to find the globally optimal way to solve the entire problem using this method. Why Are Greedy Algorithms Called Greedy? We call algorithms greedy when

hacking Featured

How Does BitTorrent Work? A Plain English Guide

No talk about downloading things on BitTorrent. Or the best clients to do so. Just a deep dive into the technical side of it. Anyone can read this article. Requires ZERO knowledge of networking or BitTorrent to read this. BitTorrent is one of the most common protocols for transferring large

Algorithms

How to Share a Secret (Diffie-Hellman-Merkle)

Diffie-Hellman-Merkle is a way to share a secret key with someone (or something) without actually sending them the key. Before we look into how we share keys let’s first look into what keys are and why we would want to invent a method to share keys without giving the

programming

The Ultimate Guide to Writing Effective Commit Messages: Best Practices and Conventional Commits

The ultimate guide to conventional commits and writing nicer commit messages

hacking Featured

How Does Tor Really Work? The Definitive Visual Guide (2023)

Today, we’re going to do a technical deep-dive into how Tor really works. No mention of how to access Tor, no mention of what might be on Tor. This is how Tor works. Without speculation and without exaggeration of what Tor is. Just a deep dive into the technical

hacking

Forcing a device to disconnect from WiFi using a deauthentication attack

This post will show you how to disable a devices connection to WiFi using a detauthentication attack.

hacking

Shodan - The Complete Guide, Featured on TryHackMe

Shodan.io is a search engine for the Internet of Things. Ever wondered how you can find publicly accessible CCTV cameras? What about finding out how many Pi-Holes are publicly accessible? Or whether your office coffee machine is on the internet? Shodan.io is the answer! Shodan scans the whole

finance

Crowdstrike

This article is not financial advice, and the only reason I am writing it is so I can re-read my reasoning. I am posting it online so if I am wrong, others can correct my reasoning. Per Lynch: Know what you own, and know why you own it Do your

finance

The Hut Group

This article is not financial advice, and the only reason I am writing it is so I can re-read my reasoning. I am posting it online so if I am wrong, others can correct my reasoning. Per Lynch: Know what you own, and know why you own it Do your

finance

Rightmove

This article is not financial advice, and the only reason I am writing it is so I can re-read my reasoning. I am posting it online so if I am wrong, others can correct my reasoning. Per Lynch: Know what you own, and know why you own it Do your

finance

Wise - Money without Borders

This article is not financial advice, and the only reason I am writing it is so I can re-read my reasoning. I am posting it online so if I am wrong, others can correct my reasoning. Per Lynch: Know what you own, and know why you own it Do your

Popular Featured

Over-engineering my document storage system with Paperless-ngx

I think the first realisation that I was getting old was when I implemented a system to store physical + digital documents and was excited about it. My previous document system looked a little something like this: Whenever someone asked me "hey can you prove you got a C in

Misconceptions Programmers Have about Names in the UK

Contrary to popular belief, in the United Kingdom, there isn't a definition of "legal name". Lord Justice Ormrod, in the case of D v B (orse D) [1979] Fam 38, in the Court of Appeal, ascertained that: It is common ground that a surname in common

grind75

98. Validate Binary Search Tree

Problem Given the root of a binary tree, determine if it is a valid binary search tree (BST). A valid BST is defined as follows: * The left subtree of a node contains only nodes with keys less than the node's key. * The right subtree of a node contains

grind75

102. Binary Tree Level Order Traversal

Problem Given the root of a binary tree, return the level order traversal of its nodes' values. (i.e., from left to right, level by level). Example 1: Input: root = [3,9,20,null,null,15,7] Output: [[3],[9,20],[15,7]] Example 2: Input: root = [1] Output:

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70. Climbing Stairs

Problem You are climbing a staircase. It takes n steps to reach the top. Each time you can either climb 1 or 2 steps. In how many distinct ways can you climb to the top? Example 1: Input: n = 2 Output: 2 Explanation: There are two ways to climb to

grind75

509. Fibonacci Number

Problem The Fibonacci numbers, commonly denoted F(n) form a sequence, called the Fibonacci sequence, such that each number is the sum of the two preceding ones, starting from 0 and 1. That is, F(0) = 0, F(1) = 1 F(n) = F(n - 1) + F(n - 2)

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589. N-ary Tree Preorder Traversal

Problem Given the root of an n-ary tree, return the preorder traversal of its nodes' values. Nary-Tree input serialization is represented in their level order traversal. Each group of children is separated by the null value (See examples) Example 1: Input: root = [1,null,3,2,4,null,5,

142. Linked List Cycle II

Problem Given the head of a linked list, return the node where the cycle begins. If there is no cycle, return null. There is a cycle in a linked list if there is some node in the list that can be reached again by continuously following the next pointer. Internally,

grind75

15. 3Sum

Problem Given an integer array nums, return all the triplets [nums[i], nums[j], nums[k]] such that i != j, i != k, and j != k, and nums[i] + nums[j] + nums[k] == 0. Notice that the solution set must not contain duplicate triplets. Example 1: Input: nums = [-1,0,1,

grind75

167. Two Sum II - Input Array Is Sorted

Problem Given a 1-indexed array of integers numbers that is already sorted in non-decreasing order, find two numbers such that they add up to a specific target number. Let these two numbers be numbers[index1] and numbers[index2] where 1 <= index1 < index2 <= numbers.length. Return the indices