#include <bits/stdc++.h>
#define ll long long
#define INF 1000000005
#define MOD 1000000007
#define EPS 1e-10
#define rep(i,n) for(int i=0;i<(int)n;++i)
#define each(a, b) for(auto (a): (b))
#define all(v) (v).begin(),(v).end()
#define fi first
#define se second
#define pb push_back
#define show(x) cout <<#x<<" = "<<(x)<<endl
#define spair(p) cout <<#p<<": "<<p.fi<<" "<<p.se<<endl
#define svec(v) cout<<#v<<":";rep(kbrni,v.size())cout<<" "<<v[kbrni];cout<<endl
#define sset(s) cout<<#s<<":";each(kbrni,s)cout <<" "<<kbrni;cout<<endl

using namespace std;

typedef pair<int,int>P;

const int MAX_N = 100005;

int main()
{
    int n,m;
    cin >> n >> m;
    if(m == 0){
        if(n == 1 || n == 2){
            cout << "Impossible\n";
        }else{
            cout << "Possible\n";
        }
    }else if(m == 1){
        cout << "Possible\n";
    }else{
        if(m == 2 && (n == 2 || n == 3)){
            cout << "Impossible\n";
        }
        if(m == 3 && (n == 3 || n == 4)){
            cout << "Impossible\n";
        }
        cout << "Possible\n";
    }
    return 0;
}