gistfile1.txt

printf "Enter two integer values:\n"

low_value = nil
high_value = nil

while !(!(low_value.nil?) && !(high_value.nil?))
  printf "#DBG B: low_value=%s, high_value=%s\n", low_value.inspect, high_value.inspect
  user_ans = STDIN.gets
  if user_ans.nil?
    STDERR.printf "\n <-- EOF! -->\n"
    exit 1
  end

  user_ans = user_ans.strip
  case user_ans
  when /^\d+$/
    if low_value.nil?
      low_value = user_ans.to_i
    else
      high_value = user_ans.to_i
    end
  else
    STDERR.printf "Invalid response:  '%s'\n", user_ans
  end

  printf "#DBG E: low_value=%s, high_value=%s\n", low_value.inspect, high_value.inspect
end # until

exit 1 if low_value.nil?
exit 1 if high_value.nil?

if low_value > high_value
  tmp = high_value
  high_value = low_value
  low_value = tmp
end

printf "%d\n", low_value
printf "%d\n", high_value