joegiralt

def special_pythagorean_triplet(num)
  (1..(num/2)).to_a.combination(3).to_a.each do |set|
    sort_set    = set.sort!
    triplet     = (sort_set[0] ** 2 + sort_set[1]**2) == sort_set[2]**2 
    equals_1000 = (sort_set.inject(:+) == num)
    
    if triplet && equals_1000 
      answer = sort_set.inject(:*)
    else
      answer = "no special triplet"  

joegiralt

def sum_square_difference(num)
  ((1..num).map{ |elem| elem ** 2 }.inject(:+) - (1..num).inject(:+) ** 2).abs
end
puts sum_square_difference(100)

joegiralt

#Functional
require 'prime'
def find_10001_prime(array)
  # array[0] incrementor
  # array[1] number of time incremetor was prime
  prime_but_not_10001 = Prime.instance.prime?(array[0]) && array[1] != 10001
  prime_10001         = Prime.instance.prime?(array[0]) && array[1] == 10001
  
  if prime_but_not_10001
    puts "#{array} prime_but_not_10001"

joegiralt

array = ['jim','jack','joe','larry','larry','larry','larry','larry', 'joe']

def count_items(array)
  hash = {}
  array.each do |name|
  
    if hash[name]
      hash[name] = hash[name] + 1
    else
      hash[name] = 1

joegiralt

def sort_and_find_copies(array)  
  array.each_with_index do |element, idx|  
    previous_idx = idx - 1  
    while previous_idx >= 0
      puts "#{array[previous_idx]} is a copy!" if  array[previous_idx] == element 
      break if array[previous_idx] <= element  
      array[previous_idx + 1] = array[previous_idx]  
      previous_idx -= 1  
    end  
    array[previous_idx + 1] = element  

joegiralt

# If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23.
# Find the sum of all the multiples of 3 or 5 below 1000.

sum = Enum.sum Enum.filter(
    Enum.to_list(1..999),
    fn(x) ->
      rem(x, 3) == 0 or rem(x, 5) == 0
    end
  )
IO.puts sum

joegiralt

set = []
(1..999).each do |num|
  if num % 3 == 0
    set.push(num)
  end
end
puts set

sum = 0
for num in set

joegiralt

class Integer
  def choose(k)
    return 0 if (k > self)
    n = self
    r = 1
    1.upto(k) do |d|
      r *= n
      r /= d
      n -= 1
    end

joegiralt

hash = {}
perfect_sqrs = []
(1..300).each do |num|
  perfect_sqrs << (num**2)
end

find_partition = lambda do |elts|
  p "ELTS: #{elts}"
  if elts.empty?
    [[]]

joegiralt

#!/bin/bash
# Pull this file down, make it executable and run it with sudo
# wget https://raw.github.com/gist/5487621/build-erlang-r16b.sh
# chmod u+x build-erlang-r16b.sh
# sudo ./build-erlang-r16b.sh

if [ $(id -u) != "0" ]; then
echo "You must be the superuser to run this script" >&2
exit 1
fi