#include<iostream>
#include<string>
#include<iomanip>
#include<cmath>
#include<vector>
#include<algorithm>

using namespace std;

#define int long long
#define rep(i,n) for(int i = 0; i < (n); i++)
#define INF ((long long)1e18)
#define MOD ((int)1e9+7)
#define endl "\n"

#define yn(f) ((f)?"Yes":"No")
#define YN(f) ((f)?"YES":"NO")

#define MAX

signed main(){
	cin.tie(0);
	ios::sync_with_stdio(false);
	cout<<fixed<<setprecision(10);
	
	int A, B, C;
	
	cin>>A>>B>>C;
	
	for(int i = 1; i <= A + B*10;i++){
		int temp = A + B*10 - i, temp2 = 0;
		temp2 = temp/10 + temp%10;
		
		for(int j = 0; j <= A; j++){
			for(int k = 0; k <= B; k++){
				int temp = j + k*10 - i, temp2 = 0;
				if(temp < 0) continue;
				if(temp/10 + temp%10  + (A-j) + (B-k) == C){
					
					cout<<i<<endl;
					return 0;
				}
			}
		}
	}
	
	cout<<"Impossible"<<endl;
	
	return 0;
}