#include <bits/stdc++.h>
#include <assert.h>
#define FOR(i,bg,ed) for(ll i=(bg);i<(ed);i++)
#define REP(i,n) FOR(i,0,n)
#define MOD 1000000007
//#define int long long
using namespace std;
typedef long long ll;
typedef vector<int> V;
typedef vector<V> VV;
const int INF = 1e9;

signed main()
{
    int N, M;
    
    cin >> N >> M;
    if (N > 3) {
        if (M > 3) {
            cout << "Possible" << endl;
        } else if (M == 0) {
            cout << "Possible" << endl;
        } else {
            //cout << "Possible" << endl;
            assert(false);
        }
    } else if (N == 3) {
        if (M == 2) {
            cout << "Impossible" << endl;
        } else {
            cout << "Possible" << endl;
        }
    } else if (N == 2) {
        if (M == 0) {
            cout << "Impossible" << endl;
        } else {
            cout << "Possible" << endl;
        }
    } else if (N == 1) {
        if (M == 0) {
            cout << "Impossible" << endl;
        } else {
            cout << "Possible" << endl;
        }
    }
}