#include <algorithm>
#include <array>
#include <cmath>
#include <iomanip>
#include <iostream>
#include <set>
#include <tuple>
#include <vector>

using namespace std;

using point = array<int, 3>;

int64_t sqr(int64_t x) { return x * x; }

struct kd_tree {
  int n;
  vector<point> P;

  kd_tree(vector<point> P) : n(P.size()), P(P) { build(0, n, 0); }

  void build(int b, int e, int spl) {
    if (e <= b)
      return;

    int m = (b + e) / 2;
    nth_element(P.begin() + b, P.begin() + m, P.begin() + e,
                [spl](auto &p, auto &q) { return p[spl] < q[spl]; });

    build(b, m, !spl);
    build(m + 1, e, !spl);
  }

  int64_t nearest(point p) {
    int64_t best = 5e18;
    point ans;

    auto go = [&](auto &self, int b, int e, int spl) {
      if (e <= b)
        return;

      int m = (b + e) / 2;
      auto &q = P[m];

      int64_t now = sqr(q[0] - p[0]) + sqr(q[1] - p[1]) + sqr(q[2] - p[2]);

      if (now > 0 && now < best) {
        best = now;
        ans = q;
      }

      if (p[spl] < q[spl]) {
        self(self, b, m, !spl);
        if (q[spl] - p[spl] < 1e-5 + sqrt(best)) {
          self(self, m + 1, e, !spl);
        }
      } else {
        self(self, m + 1, e, !spl);
        if (p[spl] - q[spl] < 1e-5 + sqrt(best))
          self(self, b, m, !spl);
      }
    };

    go(go, 0, n, 0);

    return best;
  }
};

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);

  int n;
  cin >> n;

  vector<point> points(n);
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < 3; j++)
      cin >> points[i][j];
  }

  auto kdTree = kd_tree(points);

  int64_t ans = 5e18;
  for (int i = 0; i < n; i++) {
    ans = min(ans, kdTree.nearest(points[i]));
  }

  cout << fixed << setprecision(8);
  cout << sqrt(ans) << endl;
}