#include <bits/stdc++.h>
#define int long long
using namespace std;
const int inf = 1e18, nmax = 1e5;
pair<int, int> v[nmax];
int32_t main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
cout.tie(nullptr);
int n;
cin >> n;
if (n <= 2) {
cout << -1;
return 0;
}
for (int i = 1; i <= n; i++) {
cin >> v[i].first >> v[i].second;
}
sort(v + 1, v + n + 1);
int maxx = 1;
for (int i = 2; i <= n; i++) {
if (v[i].first != v[i - 1].first)
maxx = max(maxx, abs((v[i].first - v[i - 1].first) - 1) * abs(v[i].second - v[i - 1].second));
if (v[i].second != v[i - 1].second)
maxx = max(maxx, abs(v[i].first - v[i - 1].first) * (abs(v[i].second - v[i - 1].second) - 1));
}
for (int i = 1; i <= n; i++) {
swap(v[i].first, v[i].second);
}
sort(v + 1, v + n + 1);
for (int i = 2; i <= n; i++) {
if (v[i].first != v[i - 1].first)
maxx = max(maxx, abs((v[i].first - v[i - 1].first) - 1) * abs(v[i].second - v[i - 1].second));
if (v[i].second != v[i - 1].second)
maxx = max(maxx, abs(v[i].first - v[i - 1].first) * (abs(v[i].second - v[i - 1].second) - 1));
}
cout << maxx;
return 0;
}
