#include <stdio.h>
#include <algorithm>
#include <assert.h>
#include <set>
#include <map>
#include <complex>
#include <iostream>
#include <time.h>
#include <stack>
#include <stdlib.h>
#include <memory.h>
#include <bitset>
#include <math.h>
#include <string>
#include <string.h>
#include <queue>
#include <vector>

using namespace std;

const int MaxN = 1e5 + 10;
const int MOD = 1e9 + 7;
const int INF = 1e9;

int main() {
//  freopen("input.txt", "r", stdin);
  int a, b, c, d;
  cin >> a >> b >> c >> d;
  if (a * b == c * d || a * d == b * c || a * c == b * d) {
    cout << "Possible\n";
  } else {
    cout << "Impossible\n";
  }
  return 0;
}