#include <bits/stdc++.h>
using namespace std;
mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());
const int man = 1000;
int n;
int pr[man];
long long a[man], b[man];
long long sq(long long x) {
return x * x;
}
long long rast(int i, int j) {
return sq(a[i] - a[j]) + sq(b[i] - b[j]);
}
int f(int x) {
return (x == pr[x]) ? x : pr[x] = f(pr[x]);
}
void un(int x, int y) {
x = f(x);
y = f(y);
pr[y] = x;
}
bool can(long long x) {
for (int i = 0; i < n; ++i) {
pr[i] = i;
}
for (int i = 0; i < n; ++i) {
for (int j = 0; j < n; ++j) {
if (x >= rast(i, j)) {
un(i, j);
}
}
}
set <int> s;
for (int i = 0; i < n; ++i) {
s.insert(f(i));
}
return (int)(s.size()) == 1;
}
int main() {
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
cin >> n;
for (int i = 0; i < n; ++i) {
cin >> a[i] >> b[i];
}
long long l = 0, r = 2e18;
while (l < r) {
long long md = (l + r) >> 1LL;
if (can(md) == true) {
r = md;
} else {
l = md + 1;
}
}
cout.precision(8); cout << fixed;
cout << (sqrt(l) / (long double)(2)) << "\n";
return 0;
}
