if Gem.win_platform?
  Encoding.default_external = Encoding.find(Encoding.locale_charmap)
  Encoding.default_internal = __ENCODING__

  [STDIN, STDOUT].each do |io|
    io.set_encoding(Encoding.default_external, Encoding.default_internal)
end
end

file = File.new("./three_letters.txt","r:UTF-8")

puts open_file = file.read
words = open_file.split(" ")

arr_three_letters = []
number = 0

for word in words
    if word.size == 3
      arr_three_letters << word
      number += 1
    end
end

puts "Количество слов из трех букв равно: #{number}"

puts "Слова: #{arr_three_letters.join(", ")}"