PJUllrich

Big-O Time Complexities for Elixir data structures

Map [1]

Operation	Time Complexity
Access	O(log n)
Search	O(log n)
Insertion	O(n) for <= 32 elements, O(log n) for > 32 elements [2]
Deletion	O(n) for <= 32 elements, O(log n) for > 32 elements

PJUllrich

1. Create a Droplet on e.g. DigitalOcean.
   • Make sure it has at least 1 vCPU and 1 GB of memory.
   • Mine has: 1 vCPU, 1 GB, 35 GB NVMe SSD, Premium Intel CPU, Ubuntu 24.04 LTS for $8/month on Digital Ocean
   • Choose SSH KEY AUTHENTICATION and create a new SSH key.
   • Remember the server's IPv4 address.
2. Sign up for a Container Registry e.g. on Digital Ocean for $5/mo (the 500MB free plan won't cut it)
   • Remember your username on the registry
3. Create an API Token at https://cloud.digitalocean.com/account/api/tokens for pushing images to the registry.
   • It needs to have these scopes: registry (4): delete, update, read, create
4. Install Kamal with gem install kamal

PJUllrich

#!/bin/bash
# Updates either the Elixir or erlang version everywhere in the project

set -e

if [ "$#" -ne 2 ]; then
  echo "Usage: $0 old_version new_version. Example: $0 1.15.7 1.16.1"
  exit 1
fi

PJUllrich

medal_type,medal_code,medal_date,name,gender,discipline,event,event_type,url_event,code,country_code,country,country_long
Gold Medal,1,2024-07-27,Remco EVENEPOEL,M,Cycling Road,Men's Individual Time Trial,ATH,/en/paris-2024/results/cycling-road/men-s-individual-time-trial/fnl-000100--,1903136,BEL,Belgium,Belgium
Silver Medal,2,2024-07-27,Filippo GANNA,M,Cycling Road,Men's Individual Time Trial,ATH,/en/paris-2024/results/cycling-road/men-s-individual-time-trial/fnl-000100--,1923520,ITA,Italy,Italy
Bronze Medal,3,2024-07-27,Wout van AERT,M,Cycling Road,Men's Individual Time Trial,ATH,/en/paris-2024/results/cycling-road/men-s-individual-time-trial/fnl-000100--,1903147,BEL,Belgium,Belgium
Gold Medal,1,2024-07-27,Grace BROWN,W,Cycling Road,Women's Individual Time Trial,ATH,/en/paris-2024/results/cycling-road/women-s-individual-time-trial/fnl-000100--,1940173,AUS,Australia,Australia
Silver Medal,2,2024-07-27,Anna HENDERSON,W,Cycling Road,Women's Individual Time Trial,ATH,/en/paris-2024/results/cycling-road/women-s-

PJUllrich

[
  {
    "context": "Pane",
    "bindings": {
      "ctrl-shift-tab": "pane::ActivatePrevItem",
      "ctrl-tab": "pane::ActivateNextItem",
      "cmd-shift-t": "workspace::NewTerminal"
    }
  },
  {

PJUllrich

defmodule MyApp.Http do
  @moduledoc """
  Exposes functions to make HTTP requests and optionally cache the response.

  If you want to cache the request, simply add `cache: true` to the 
  request options. You can also define an option time-to-live (TTL) with
  `cache_ttl: ttl_in_milliseconds`. The default TTL is 5min.

  Only caches 2xx responses.
  """

PJUllrich

defmodule Attack.Worker do
  use GenServer

  require Logger

  def start_link(init_args) do
    GenServer.start_link(__MODULE__, [init_args])
  end

  def init(_args) do

PJUllrich

#!/bin/bash

IP=`hostname -I | awk '{print $1}'`
MESSAGE="Pi ${HOSTNAME} fully booted. New IP: $IP"
TITLE="`whoami`@${HOSTNAME}"

APP_TOKEN="YOUR_APP_TOKEN_HERE"
USER_TOKEN="YOUR_USER_TOKEN_HERE"

wget https://api.pushover.net/1/messages.json --post-data="token=$APP_TOKEN&user=$USER_TOKEN&message=$MESSAGE&title=$TITLE" -qO- > /dev/null 2>&1 &

PJUllrich

The Code

Mix.install([{:benchee, "~> 1.0", only: :dev}, {:plug, "~> 1.14"}])

iterations = 10

# Compares the strings with "=="
# Returns 'nil' to minimize time spent on allocating and moving around memory
variable_compare = fn left, right -> 
  for _ <- 1..iterations, do: left == right

PJUllrich

{
  "version": "2.0.0",
  "tasks": [
    {
      "label": "Build",
      "type": "shell",
      "command": "mix compile",
      "problemMatcher": ["$mixCompileError", "$mixCompileWarning"],
      "group": {
        "kind": "build",