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class AdminController < ApplicationController
  set_current_tenant_through_filter
  
  before_action :authenticate_user!

  before_filter :load_tenant
  
  def load_tenant
    begin
      tenant = if session[:current_tenant]

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class GameOfLife
  def initialize(size, iterations)
    @square_size = size
    @max_iterations = iterations
  end

  def run
    # Set up the initial array.
    @board = Array.new(@square_size)

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# Snake Case multi-process!

defmodule SnakeCase do
  def multi do
    Agent.start_link(fn -> 0 end, name: __MODULE__)
    ranges = Enum.chunk(0..round(:math.pow(2, 20)), 262144)
    tasks = Enum.map ranges, fn range ->
      Task.async(fn -> subrange(range) end)
    end
    for task <- tasks, do: Task.await(task)

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# From the ACR 2016 coding challenge.

defmodule SnakeCase do

  @doc """
  Brute force, single process.
  """
  def single do
    range = 0..round(:math.pow(2, 20))
    count = Enum.count(range, fn x -> check_one_bits(x) == 10 end)

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module TreeGenerator
  def self.generate_tree
    pages = all.select('id, name, depth, parent_id, sort_order').order('sort_order ASC')
    ordered_pages = ActiveSupport::OrderedHash.new

    pages.each do |page|
      ordered_pages[page.id] = {page: page, children: generate_children(page.id, pages)} if page.depth == 0
    end

    ordered_pages

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module TreeGeneratorOptimized
  def self.generate_tree
    pages = all.select('id, name, depth, parent_id, sort_order').order('sort_order ASC')
    ordered_pages = ActiveSupport::OrderedHash.new

    parent_hash = Hash.new
    pages.each do |page|
      parent_hash[page.parent_id] = Array.new if parent_hash[page.parent_id].nil?
      parent_hash[page.parent_id].push(page) unless page.nil?
    end

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def odd(n)
  n%2 != 0
end

# Here's what we expect:
if a = odd(5) and a == true
  puts "a is odd"
end
# => "a is odd"

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# &&
puts "test".is_a?(String) && 54+33 # => 87
puts "test".is_a?(String) && true # => true
puts 54+33 && "test".is_a?(String) # => true
puts true && "test".is_a?(Integer) # => false
puts "test".is_a?(Integer) && true # => false

# ||
puts "true" || "test".is_a?(String) # => "true"
puts "true".size == 12 || "test".is_a?(String) # => true

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return Photo.find(params[:photo][:id]) or Photo.new
# Valid parameter: instance from database
# Invalid parameter: new instance

return photo = Photo.find(params[:photo][:id]) and photo.update(comment: params[:photo][:comment]) and photo
# Valid ID and successful update: photo instance
# Valid ID and failed update: result of update
# Invalid ID: nil

# Yes, I work in Rails. You got a problem with that?!?

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class Random < ActiveRecord::Base
  after_initialize :check_data
  after_initialize :save_data
  
  before_save :check_data
  before_save :save_data
  
  private
  
  def check_data