#include<iostream>
#include<algorithm>
using namespace std;
using lint=int64_t;

int main()
{
	int A,B,C;

	cin >> A >> B >> C;

	int ans=1e4;
	for(int a=0;a<=A;a++)
	{
		for(int b=0;b<=B;b++)
		{
			for(int g=1;g<=a+10*b;g++)
			{
				int rest=a+10*b-g;
				int ra=rest%10;
				int rb=rest/10;
				if(A+B-a-b+ra+rb==C)
					ans=min(ans,g);
			}
		}
	}
	if(ans==1e4)cout << "Impossible";
	else cout << ans;
	cout << endl;
	return 0;
}