#include "bits/stdc++.h"
#define in std::cin
#define out std::cout
#define rep(i,N) for(LL i=0;i<N;++i)
typedef long long int LL;

int main()
{
	LL A, B, C;
	in >> A >> B >> C;

	for (LL i = 1; i <= A + 10 * B; ++i)
	{
		for (LL a = 0; a <= A; ++a)
		{
			for (LL b = 0; b <= B; ++b)
			{
				LL charge = (a + 10 * b) - i;
				if (charge < 0) continue;
				if (charge / 10 + charge % 10 + (A - a) + (B - b) == C)
				{
					out << i << std::endl;
					return 0;
				}
			}
		}
	}
	out << "Impossible" << std::endl;
}