# frozen_string_literal: true

X = gets.chomp.chars.map(&:to_i).sort

if X.uniq.size == 1 || X[-2].zero?
  puts(-1)
else
  result = []
  swapped = false
  X.each_cons(2) do |a, b|
    if swapped
      result << b
    elsif a != b
      result << b << a
      swapped = true
    else
      result << a
    end
  end
  puts result.reverse.join
end