#include <bits/stdc++.h>
using namespace std;
const int N = 3010;
bitset<3000> q[N];
pair<int, pair<int, int> > p[N * N / 2];
int x[N], y[N], n, c;
int main() {
  scanf("%d", &n);
  for (int i = 0; i < n; ++i) scanf("%d%d", &x[i], &y[i]);
  for (int i = 1; i < n; ++i)
    for (int j = 0; j < i; ++j)
      p[c++] = make_pair(
          ((x[i] - x[j]) * (x[i] - x[j])) + ((y[i] - y[j]) * (y[i] - y[j])),
          make_pair(i, j));
  sort(p, p + c);
  reverse(p, p + c);
  for (int i = 0; i < c; ++i) {
    int a = p[i].second.first, b = p[i].second.second;
    if ((q[a] & q[b]).any()) {
      printf("%.12lf\n", sqrt(p[i].first + .0) / 2.);
      return 0;
    }
    q[a][b] = q[b][a] = 1;
  }
}
