#include<iostream>
using namespace std;
int a,b,c,d;
main()
{
	cin>>a>>b>>c>>d;
	if(d==10)
	{
		cout<<"Impossible"<<endl;
		return 0;
	}
	cout<<"Possible"<<endl;
	int ans=0;
	c=0;
	d=50;
	if(b==0)b=a,a=0,d=100;
	while(b>0)
	{
		ans+=d;
		b--;
		c++;
		if(c%100==0)d*=2;
		if(b==0)b=a,a=0,d*=2;
	}
	cout<<ans<<endl;
}