#include <bits/stdc++.h>
using namespace std;
long long a[60][60], b[60][60], n, m;
int main() {
  cin >> n >> m;
  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= m; j++) {
      cin >> a[i][j];
    }
  }
  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= m; j++) {
      cin >> b[i][j];
    }
  }
  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= m; j++) {
      long long mn = min(a[i][j], b[i][j]);
      long long mx = max(a[i][j], b[i][j]);
      a[i][j] = mn;
      b[i][j] = mx;
    }
  }
  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= m; j++) {
      if (a[i][j] <= a[i][j - 1] || a[i][j] <= a[i - 1][j])
        return cout << "Impossible", 0;
      if (b[i][j] <= b[i][j - 1] || b[i][j] <= b[i - 1][j])
        return cout << "Impossible", 0;
    }
  }
  cout << "Possible";
  return 0;
}
