hash_collision.rb

require 'digest/sha1'

bob_texts_c = []
mallory_texts_c = []
bob_texts = {}
mallory_texts = {}

bob_text = 'Wyplacic Bobowi 100 zlotych.'
mallory_text = 'Wyplacic Mallory 100 zlotych.'

letters = ('a'..'z').to_a
puts letters.combination(2).to_a.length

letters.combination(2).each_with_index do |word, index|
	bob_texts_c.push(Digest::SHA1.hexdigest(bob_text + word.join)[-4, 4])
	bob_texts[Digest::SHA1.hexdigest(bob_text + word.join)[-4, 4]] = (bob_text + word.join)
	mallory_texts_c.push(Digest::SHA1.hexdigest(mallory_text + word.join)[-4, 4])
	mallory_texts[Digest::SHA1.hexdigest(mallory_text + word.join)[-4, 4]] = (mallory_text + word.join)

end

(bob_texts_c & mallory_texts_c).each do |text|
	puts bob_texts[text] + " = " + mallory_texts[text]
end