//KZNS
#include <cstdio>
#include <vector>
#include <utility>
#include <algorithm>
using namespace std;
#define Nmax 1003
inline int diss(int a, int b, int c, int d) {
	return (a-c)*(a-c) + (b-d)*(b-d);
}
typedef pair<int, pair<int, int> > pr;
int N;
int A[Nmax][2];
vector<pr> ls;
void init() {
	scanf("%d", &N);
	for (int i = 1; i <= N; i++) {
		scanf("%d %d", &A[i][0], &A[i][1]);
		for (int j = 1; j < i; j++)
			ls.push_back(make_pair(diss(A[j][0], A[j][1], A[i][0], A[i][1]), make_pair(i, j)));
	}
}
int fa[Nmax];
int FA(int x) {
	if (fa[x] == x)
		return x;
	return fa[x] = FA(fa[x]);
}
void sb(int a, int b) {
	if (FA(a) != FA(b)) {
		fa[fa[a]] = fa[b];
		N--;
	}
}
void work() {
	sort(ls.begin(), ls.end());
	for (int i = 1; i <= N; i++)
		fa[i] = i;
	pr u;
	for (int i = 0; i < ls.size(); i++) {
		u = ls[i];
		sb(u.second.first, u.second.second);
		if (N <= 1) {
			printf("%d\n", u.first);
			return;
		}
	}
}
int main() {
	freopen("moocast.in", "r", stdin);
	freopen("moocast.out", "w", stdout);
	init();
	work();
	return 0;
}
//UBWH