#include <bits/stdc++.h>
using namespace std;
#define int long long
vector<int> tree;
int fin(int n) {
if (tree[n] == n) return n;
return tree[n] = fin(tree[n]);
}
void join(int a, int b) {
a = fin(a);
b = fin(b);
if (a == b) return;
tree[b] = a;
}
signed main() {
int n, x, y;
cin >> n;
vector<pair<int, int>> coords;
for (int i = 0; i < n; i++) {
cin >> x >> y;
coords.push_back({ x, y });
}
priority_queue<pair<long double, pair<int, int>>, vector<pair<long double, pair<int, int>>>, greater<pair<long double, pair<int, int>>>> pq;
for (int i = 0; i < n; i++)
for (int j = i + 1; j < n; j++)
pq.push({ pow((coords[i].first - coords[j].first) * (coords[i].first - coords[j].first) + (coords[i].second - coords[j].second) * (coords[i].second - coords[j].second), (long double)0.5), {i, j} });
for (int i = 0; i < n; i++)
tree.push_back(i);
long double ans = -1;
while (!pq.empty()) {
if (fin(pq.top().second.first) != fin(pq.top().second.second)) {
ans = max(ans, pq.top().first);
join(pq.top().second.first, pq.top().second.second);
}
pq.pop();
}
cout << ans / 2 << '\n';
}
