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John Cipriano johncip

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@johncip
johncip / 264.java
Last active February 17, 2016 06:02
Count on Cantor
/*
* 264 - Count on Cantor
*
* Given an input value N, print the Nth term in Cantor's enumeration.
*
* There may be a simpler closed form of this. However, what strikes me as
* possible right now is: we figure out what diagonal n is on, which gives us
* the beginning of that diagonal (1/2, 3/1, 1/4, 5/1, etc.). Then, we adjust
* the numerator and denominator based on the distance from the first term in
* the diagonal and the direction it takes (up-right for odd, down-left for
@johncip
johncip / uva-fast-io
Created May 25, 2014 08:27
Contest problem fast I/O template
/*
* Title
*/
import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class Main {
@johncip
johncip / name-length-histogram.txt
Last active January 7, 2016 22:39
Name distribution
User name metrics
Bin width: 1
Each # represents 500 users.
LENGTH OF FIRST NAME
====================
bins: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63]
freqs: [36, 510, 2547, 5905, 10086, 11103, 9461, 5363, 3918, 2780, 3515, 3655, 3609, 3213, 2246, 1469, 968, 576, 410, 253, 189, 162, 102, 57, 51, 42, 31, 24, 15, 4, 1, 4, 2, 2, 0, 1, 1, 0, 1, 1, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1]
01:
02: #
@johncip
johncip / print_fixtures.rb
Last active February 17, 2016 06:01
Print fixtures used
log = StringIO.new
ActiveRecord::Base.logger = Logger.new(log)
Gradescope::Application.config.colorize_logging = false
RSpec.configure do |config|
config.after :suite do
lines = log.tap(&:rewind).readlines.to_a
matching = lines.map do |line|
next unless line =~ /Load/
@johncip
johncip / viewer_components.opml
Created March 3, 2016 01:53
<?xml version="1.0"?>
<opml version="2.0">
<head>
<ownerEmail>[email protected]</ownerEmail>
</head>
<body>
<outline text="div#assignment-submission-app" >
<outline text="(modals)" />
<outline text="&lt;b&gt;AssignmentSubmissionViewer&lt;/b&gt;" _note="&lt;b&gt;div#assignment-submission-show&lt;/b&gt;" >
<outline text="PageViewerContainer" _note="div#assignment-submission-viewer&#10;(merge with child if possible)" >
@johncip
johncip / table_with_fixed_header.sass
Last active April 21, 2016 01:34
Pure-CSS fixed table headers
table.fixed-header
table-layout: fixed
border-collapse: collapse
thead tr
display: block
position: relative
tbody
display: block
overflow: auto
width: 100%
@johncip
johncip / browserify_react_lib.sh
Last active April 22, 2016 09:31
Browserify 3rd-party React components found on npm
# Browserify 3rd-party React components found on npm
# (prevents React & ReactDOM from being bundled)
export PACKAGE='simple-react-modal' # npm package
export EXPORT_NAME='SimpleReactModal' # will end up on window with this name
mkdir project && cd project
npm init -f
npm install -D browserify react react-dom
@johncip
johncip / install_guest_additions.sh
Last active May 26, 2016 00:50
Install VirtualBox Guest Additions on Ubuntu
# Install VirtualBox guest additions on Ubuntu
# https://www.vagrantup.com/docs/virtualbox/boxes.html
VB_VERSION='5.0.20'
wget "http://download.virtualbox.org/virtualbox/$VB_VERSION/VBoxGuestAdditions_$VB_VERSION.iso"
sudo mkdir /media/VBoxGuestAdditions
sudo mount -o loop,ro "VBoxGuestAdditions_$VB_VERSION.iso" /media/VBoxGuestAdditions
sudo sh /media/VBoxGuestAdditions/VBoxLinuxAdditions.run
rm "VBoxGuestAdditions_$VB_VERSION.iso"
@johncip
johncip / rails_eager_load.md
Last active December 28, 2024 15:12
Active Record eager loading strategies

N+1 query problem

  • ORMs make it easy to a query per loop iteration, which we want to avoid

eager_load

  • single query (left outer join)
  • can reference the other table's columns in where

preload

  • a few queries (one per table)
  • typically faster
@johncip
johncip / pronto_hack.rb
Created April 28, 2017 21:35
❯ vi /usr/local/lib/ruby/gems/2.3.0/gems/pronto-0.8.2/lib/pronto/formatter/text_formatter.rb
# change line 17 to ...
# "[#{message.runner.title}] #{format_location(message)} #{format_level(message)}: #{message.msg}".strip
❯ pronto run -r reek
Running Pronto::Reek
[reek] app/decorators/course_membership_decorator.rb:21 I: Is controlled by argument 'current_user' (ControlParameter)