x = gets.chomp.split("").sort
n = x.size
(n-1).times do |i|
    if x[i] != x[i+1] && (i != n-2 || x[i] != "0")
        x[i],x[i+1] = x[i+1],x[i]
        puts x.reverse.join("")
        exit
    end
end
puts "-1"