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Sieve of Eratosthenes

A Ruby method to find all prime numbers within a range using the Sieve of Eratosthenes.

Input: An integer defining upper boundary of range

Output: An array of the prime numbers within the range

Steps:

• Create an array of values 2..n where n is upper boundary of range
• Outer Loop:
• starting from the first prime number, 2, loop through the values of the array
• for any nil values, skip to the next value

jergagon1

# Ruby linear search method
# Input: an array and a desired value
#   the array is not necessarily sorted
# Output: the index of the desired value or nil if the desired value does not occur

def linear_search input_array, desired_value
  current_index = 0
  while current_index < input_array.length
    if input_array[current_index] == desired_value
      return current_index

jergagon1

# Ruby binary search method
# Input: a sorted array and the desired value
# Output: the index of the desired value or nil if it does not occur
# Edge Cases:
# Value is within upper and lower range of array but does not occur
# Value is outside upper range of array
# Value is outside lower range of array
# Input array is empty
# input array is not sorted -> to test would have to sort array and check equality
#   for efficiency, assuming input sorted

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def bubble_sort num_array
  array_sorted = false
  current_index = 0
  index_to_compare = 1
  until array_sorted
    change_this_loop = false
    (num_array.length-1).times do |counter|
      first_value = num_array[current_index + counter]
      second_value = num_array[index_to_compare + counter]
      if first_value > second_value

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# Ruby method to detect if input is palindrome
# Input: string
# Output: boolean
# Edge cases
# Spaces and punctuation -> scrub input with helper method
# Number input -> convert to string in scrub string

def scrub_string str
  str = str.to_s if !str.is_a?String
  str = str.gsub(/\W|\_/, "").downcase

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# Ruby Method FizzBuzz
# Input: An optional array of numbers, if not provided use array of numbers in range 1 to 100
# Output: An array of numbers with the following exceptions
#   Any number evenly divisible by 3 and 5 is replaced with string "FizzBuzz"
#   Any number evenly divisble by 3 and not evenly divisible by 5 is replaced with string "Fizz"
#   Any number evenly divisble by 5 and not evenly divisible by 3 is replaced with string "Buzz"

def fizzbuzz (num_array = (1..100).to_a)
  results = num_array.map do |num|
    if num % 3 == 0 && num % 5 == 0

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# Monkey patch a map and map! method
class Array
  def my_map
    mapped_array = []
    self.each { |element| mapped_array.push yield element }
    mapped_array
  end

  def my_map!
    self.length.times do |i|

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$(document).ready(function() {

  /********************* Model **********************/

  var Die = function () {
    this.value = 0;
  };

  Die.prototype.roll = function() {
      this.value = Math.floor((Math.random()*6)+1);

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NUMERAL_HASH = {
  1 => "I",
  5 => "V",
  10 => "X",
  50 => "L",
  100 => "C",
  500 => "D",
  1000 => "M"
}

jergagon1

# Manual selection sort method in ruby
# Big O time = O(n**2)
# Big O space = O(1)

##############################################
# 1st pass: nested while loops
##############################################

def selection_sort num_array
  i = 0