#include "bits/stdc++.h"

using namespace std;

void solve(void)
{
	int a, b, c;
	cin >> a >> b >> c;
	int ans = 10000;
	for (int x = 0; x <= a; x++)
		for (int y = 0; y <= b; y++)
			for (int z = 1; z <= x+10*y; z++)
			{
				int turi = x + 10 * y - z;
				int na = a - x + turi % 10;
				int nb = b - y + turi / 10;
				if (na + nb == c)
				{
					ans = min(ans, z);
				}
			}
	if (ans < 10000)
	{
		cout << ans << endl;
	}
	else
	{
		cout << "Impossible" << endl;
	}
}

int main()
{
	solve();
	//cout << "yui(*-v・)yui" << endl;
	return 0;
}