#include <bits/stdc++.h>
using namespace std;
int pre[4005];
void init() {
  for (int i = 1; i <= 4000; i++) pre[i] = i;
}
int find(int x) {
  if (pre[x] != x) {
    pre[x] = find(pre[x]);
  }
  return pre[x];
}
void Union(int x, int y) {
  int fx = find(x);
  int fy = find(y);
  pre[fx] = fy;
}
struct event {
  int x, y;
  int t;
  event() {}
  event(int xx, int yy, int tt) {
    x = xx;
    y = yy;
    t = tt;
  }
  bool operator<(const event a) const {
    if (x == a.x) {
      if (y == a.y) return t > a.t;
      return y < a.y;
    }
    return x < a.x;
  }
};
event e[4000000 + 5];
int n, m;
struct point {
  int x, y;
};
point r[2005], b[2005];
int cal(point a, point b) {
  int t1 = (int)ceil(fabs(b.y + b.x - a.y - a.x) / 2.0);
  int t2 = (int)ceil(fabs(a.y - a.x - b.y + b.x) / 2.0);
  return max(t1, t2);
}
bool cmp(event a, event b) { return a.t < b.t; }
int main() {
  init();
  scanf("%d%d", &n, &m);
  for (int i = 0; i < n; i++) scanf("%d%d", &b[i].x, &b[i].y);
  for (int i = 0; i < m; i++) scanf("%d%d", &r[i].x, &r[i].y);
  for (int i = 0; i < n; i++)
    for (int j = i + 1; j < n; j++) {
      if (b[i].x - b[j].x == b[j].y - b[i].y) {
        Union(i, j);
      }
    }
  for (int i = 0; i < m; i++)
    for (int j = i + 1; j < m; j++) {
      if (r[i].x - r[j].x == r[i].y - r[j].y) {
        Union(n + i, n + j);
      }
    }
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) {
      e[i * m + j] = event(find(i), find(n + j), cal(b[i], r[j]));
    }
  }
  sort(e, e + n * m);
  vector<event> vec;
  event now = e[0];
  for (int i = 1; i <= n * m; i++) {
    if (i == n * m) {
      vec.push_back(now);
      break;
    } else {
      if (e[i].x == now.x && e[i].y == now.y) {
        now = e[i];
      } else {
        vec.push_back(now);
        now = e[i];
      }
    }
  }
  sort(vec.begin(), vec.end(), cmp);
  for (int i = 0; i < vec.size(); i++) {
    if (find(vec[i].x) == find(vec[i].y)) {
      printf("%d\n", vec[i].t);
      return 0;
    } else {
      Union(vec[i].x, vec[i].y);
    }
  }
  printf("Poor Sereja!\n");
  return 0;
}
