a, b, c = gets.split.map(&:to_i)

INF = 1000000000
ans = INF
(a + 1).times do |i|
    (b + 1).times do |j|
        hoge = i + 10 * j
        1.upto(hoge) do |k|
            foo = hoge - k
            cnt = foo / 10 + foo % 10 + a + b - i - j
            if cnt == c
                ans = [ans, k].min
            end
        end
    end
end

if ans == INF
    puts "Impossible"
else
    p ans
end