typing.rb

require 'io/console'

print('original: ')
original = STDIN.noecho(&:gets)
puts

loop do
  print('input: ')
  input = STDIN.noecho(&:gets)
  puts

  if original == input
    puts "\e[32mOK\e[0m"
  else
    puts "\e[31mNG\e[0m"
  end
rescue Interrupt
  exit
end