#include<iostream>
#include<algorithm>

using namespace std;

int mul = 1; //1倍
int sum = 0;
int combo = 0;
void calc(int a, int plus) {
    while (a--) {
        sum += plus * mul;
        combo++;
        if (combo == 100) { combo = 0; mul *= 2; }
    }
}
int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    int a, b, c, d;
    cin >> a >> b >> c >> d;
    if (d >= 10) {
        cout << "Impossible" << endl;
        return 0;
    }
    calc(b, 50); calc(a, 100);
    cout << "Possible" << endl;
    cout << sum << endl;
}