#include <bits/stdc++.h>
using namespace std;

int main() {
  string s, t; cin >> s >> t;
  char a = s.at(s.size()-1);
  char b = t.at(t.size()-1);
  if((a+b) % 2 == 0)cout << "Possible" << endl;
  else cout << "Impossible" << endl;
}