#include <bits/stdc++.h>
using namespace std;
pair<int, int> p[5];
int main() {
  int n;
  cin >> n;
  for (int i = 0; i < n; i++) cin >> p[i].first >> p[i].second;
  if (n == 1) return cout << -1, 0;
  if (n == 2) {
    if (p[0].first == p[1].first || p[0].second == p[1].second)
      return cout << -1, 0;
    cout << abs(p[0].first - p[1].first) * abs(p[0].second - p[1].second);
    return 0;
  }
  if (n == 3) {
    int ans = 0;
    for (int i = 0; i < 3; i++)
      ans = max(
          ans,
          max(max(abs(p[i].first - p[0].first) * abs(p[i].second - p[0].second),
                  abs(p[i].first - p[1].first) *
                      abs(p[i].second - p[1].second)),
              abs(p[i].first - p[2].first) * abs(p[i].second - p[2].second)));
    return cout << ans, 0;
  }
  cout << max(
      max(abs(p[0].first - p[1].first) * abs(p[0].second - p[1].second),
          abs(p[0].first - p[2].first) * abs(p[0].second - p[2].second)),
      abs(p[0].first - p[3].first) * abs(p[0].second - p[3].second));
  return 0;
}
