#include <iostream>
#include<vector>
#include<algorithm>

using namespace std;

long long hyp(long long a, long long b){
	return a * a + b * b;
}

int uni[1001];

int getuni(int a){
	if (uni[a] < 0) return a;
	else return uni[a] = getuni(uni[a]);
}

int connect(int a, int b){
	a = getuni(a);
	b = getuni(b);
	if (a == b) return 0;
	if (uni[a] > uni[b]) swap(a, b);
	uni[a] += uni[b];
	uni[b] = a;
	return 1;
}


int main() {
	int N;
	int x[1000], y[1000];
	long long dist[1000][1000];
	cin >> N;

	for (int i = 0; i < N; i++)
	{
		cin >> x[i] >> y[i];
	}

	vector<pair<long long, pair<int,int> > > v;
	for (int i = 0; i < N - 1; i++)
	{
		for (int j = i + 1; j < N; j++)
		{
			long long temp = (long long)sqrt(hyp(x[i] - x[j], y[i] - y[j]));
			temp -= temp % 10;
			while (temp * temp < hyp(x[i] - x[j], y[i] - y[j])) temp += 10;
			dist[i][j] = temp;
			v.push_back(make_pair(temp, make_pair(i, j)));
		}
	}

	long long ans = 0;
	
	sort(v.begin(), v.end());

	for (int i = 0; i < N; i++)
	{
		uni[i] = -1;
	}

	for (int i = 0; i < v.size(); i++)
	{
		if (connect(v[i].second.first, v[i].second.second)){
			ans = v[i].first;
		}
		if (getuni(0) == getuni(N - 1)) break;
	}

	cout << ans << endl;
	cin >> ans;
}