#include <iostream>
using namespace std; //cin, coutを使う
int main(){
    int H, S;
    cin >> H >> S;
    if ((H + S) % 4 == 0) {
        cout << "Possible" << endl;
    } else if ((H + S) % 4 == 1) {
        cout << "Impossible" << endl;
    } else if ((H + S) % 4 == 2) {
        cout << "Impossible" << endl;
    } else if ((H + S) % 4 == 3) {
        cout << "Possible" << endl;
    }
}