#!/usr/bin/env ruby
# frozen_string_literal: true

class Main
  def run
    @sum = 0

    $stdin.each_line do |line|
      nums = line.chomp.each_char.map(&:to_i)
      first_digit = nums[0..-2].max
      second_digit = nums[nums.find_index(first_digit) + 1..].max
      @sum += "#{first_digit}#{second_digit}".to_i
    end

    puts @sum
  end
end

Main.new.run