#include <iostream>
using namespace std;

int main(){
  int A, B, C;
  cin >> A >> B >> C;
  int t = A + B*10;
  int ans = 1e9;
  for(int i = 0; i <= min(A+9,C); ++i){
    int j = C-i;
    if(i+j*10 >= t) continue;
    if(B-j > t-i-j*10) continue;
    //cerr << i << " " << j << " " << i+j*10 << endl;
    ans = min(ans,t-i-j*10);
  }
  if(ans == 1e9) cout << "Impossible" << endl;
  else cout << ans << endl;
}