#include <iostream>
#include <cassert>
int main()
{
    int A, B, C;
    std::cin >> A >> B >> C;
    assert(0 <= A and A <= 20);
    assert(0 <= B and B <= 20);
    assert(0 <= C and C <= 100);
    for (int price = 1; price <= A + B * 10; price++) {
        for (int a = 0; a <= A; a++) {
            for (int b = 0; b <= B; b++) {
                const int pay = a + 10 * b;
                if (pay < price) { continue; }
                const int back = pay - price;
                const int pa = back % 10;
                const int pb = back / 10;
                const int coin = (A - a + pa) + (B - b + pb);
                if (coin == C) {
                    std::cout << price << std::endl;
                    return 0;
                }
            }
        }
    }
    std::cout << "Impossible" << std::endl;
    return 0;
}