part1.rb

def palindrome? str
  str.downcase!
  # gsub stands for "global substitution" and replaces all occurrences
  # of the matching regex with the given string. Here, we want all "non-word"
  # characters to be removed from the string
  str.gsub! /[\W]/, ""
  # If the forward and backward versions are the same, it's a palindrome
  str == str.reverse
end

puts palindrome?("hello world")
puts palindrome?("A man, a plan, a canal -- Panama")

def count_words str
  hash = Hash.new(0)

  str.scan(/\w+/).each do |match|
    hash[match.downcase] += 1
  end

  hash
end

puts count_words("hello world")
puts count_words("A man, a plan, a canal -- Panama")