malchak

# Question:

  # Suppose you have an array of 99 numbers. 
  # The array contains the digits 1 to 100 with one digit missing. 
  # Write four different algorithms to compute the missing number. 
  # Two of these should optimize for low storage and two of these should optimize for fast processing.
  # (Keep in mind, there are no duplicates and the array is not already sorted.)

#######################################################

joyrexus

Sans jQuery

Events

// jQuery
$(document).ready(function() {
  // code
})

shunchu

t = 236 # seconds
Time.at(t).utc.strftime("%H:%M:%S")
=> "00:03:56"

# Reference
# http://stackoverflow.com/questions/3963930/ruby-rails-how-to-convert-seconds-to-time

jordan-brough

# See http://jordan.broughs.net/archives/2012/07/enumerablecount_by-for-ruby

# Ruby >= 1.8.7 (incl 1.9.x)

module Enumerable
  def count_by(&block)
    Hash[group_by(&block).map { |key,vals| [key, vals.size] }]
  end
end

rstacruz

Rails Models

Generating models

$ rails g model User

Associations

belongs_to

has_one