#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define rep(i,n) for(int (i)=0;(i)<(n);(i)++)
#define repeat(i,s,n) for(int (i)=s; (i)<(n); (i)++)
#define revrep(i,n) for(int (i)=(n)-1;i>=0; i--)

bool check(int a, int b, int c, int aa, int bb,int x) {
  int y = aa+10*bb;
  if(y==0|y<x)
    return false;
  int aaa =(y-x)%10;
  int bbb = (y-x)/10;
  return (a-aa+aaa)+(b-bb+bbb)==c;
}

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  cout<<setprecision(std::numeric_limits<float>::max_digits10);
  int a,b,c;
  cin>>a>>b>>c;
  int ans = 1e9;
  rep(aa,a+1) {
    rep(bb,b+1) {
      repeat(x,1,10000) {
	if(check(a,b,c,aa,bb,x)) {
	  ans = min(ans,x);
	}
      }
    }
  }
  if(ans==1e9)
    cout << "Impossible" << endl;
  else
    cout << ans << endl;
  return 0;
}