#include <bits/stdc++.h>
#define pb push_back
#define pf push_front
using namespace std;
#define F first
#define S second
typedef long long ll;
#define pii pair <int, int>
#define pll pair <ll, ll>
typedef long double ld;
const ll N = 1e5 + 100, M = 4096 + 10, len = 315, inf = 1e18;
const ll mod = 1e9 + 7;
ll um(ll a, ll b){
	return (1LL * a * b) % mod;
}
ll subr(ll a, ll b){
	return ((1LL * a - b) % mod + mod) % mod;
}
pll a[N];
ll n;
ll calc(ll x, ll b, ll c){
	return abs(a[x].S - a[b].S) * abs(a[c].F - a[x].F);
}
ll cc(ll x, ll b, ll c){
	return abs(a[x].F - a[b].F) * abs(a[c].S - a[x].S);
}
void subtask3(){
	vector <ll> v1, v2;
	for(ll i = 0; i < n; i++){
		v1.pb(a[i].F);
	}
	for(ll i = 0; i < n; i++){
		v2.pb(a[i].S);
	}
	sort(v1.begin(), v1.end());
	sort(v2.begin(), v2.end());
	ll a1 = 0, a2 = 0;
	for(int i = 1; i < n; i++){
		if(v1[i] != v1[i - 1]){
			if(a1 == 0) a1 = v1[i] - v1[i - 1];
			else a1 = __gcd(a1, v1[i] - v1[i - 1]);
		}
		if(v2[i] != v2[i - 1]){
			if(a2 == 0) a2 = v2[i] - v2[i - 1];
			else a2 = __gcd(a2, v2[i] - v2[i - 1]);
		}
	}
	if(a1 == 0 || a2 == 0){
		cout << -1;
	} else{
		cout << a1 * a2;
	}
}
int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(nullptr);
	cout.tie(nullptr);
	cin >> n;
	bool s4 = true;
	for(ll i = 0; i < n; i++){
		cin >> a[i].F >> a[i].S;
	}
	if(n <= 2){
		cout << -1;
		return 0;
	}
	ll px = 0, py = 0, dy = 0;
	for(ll i = 1; i < n; i++){
		a[i].F -= a[0].F;
		a[i].S -= a[0].S;
		if(a[i].F < 0){
			a[i].F *= -1;
			a[i].S *= -1;
		}
		if(a[i].F){
			px = a[i].F;
			py = a[i].S;
		}
	}
	if(px == 0){
		cout << -1;
		return 0;
	}
	
	for(ll i = 1; i < n; i++){
		while(a[i].F){
			ll k = px/a[i].F;
			px -= k * a[i].F;
			py -= k * a[i].S;
			swap(a[i].F, px);
			swap(a[i].S, py);
		}
		if(a[i].S) dy = __gcd(dy, abs(a[i].S));
	}
	if(py == 0) cout << -1;
	else cout << abs(dy * px);
  return 0;
}