#include <bits/stdc++.h>

//{ START
using namespace std;
#define int int64_t
#define rep(i, a, n) for (int i = (a); i < (n); ++i)
#define reps(i, a, n) for (int i = (a); i > (n); --i)
#define arep(i, x) for (auto &&i : (x))
#define irep(i, x) for (auto i = (x).begin(); i != (x).end(); ++i)
//降順はgreater<T>()
#define all(x) (x).begin(), (x).end()
#define rv(s) reverse((s).begin(), (s).end())
// gcd lcmはそのままok
#define gcd(a, b) __gcd(a, b)
#define bits(n) (1 << (n))
#define pcnt(x) __builtin_popcountll(x)
//配列内等要素削除
#define unique(x) (x).erase(unique(x).begin(),(x).end()),(x).end())
#define Fixed(n) fixed << setprecision(n)
//総和
#define sowa(n) ((n) * ((n) + 1)) / 2
#define pb(x, a) (x).push_back(a)
#define fb(x, a) (x).push_front(a)
#define eb(x, a) (x).emplace_back(a)
#define F first
#define S second
#define cauto const auto &
using Pii = pair<int, int>;
using Graph = vector<vector<Pii>>;
template <class T>  //昇順
using min_heap = priority_queue<T, vector<T>, greater<T>>;
template <class T>  //降順
using max_heap = priority_queue<T>;
template <class A, class B>
using umap = unordered_map<A, B>;
template <class A>
using uset = unordered_set<A>;
template <typename A, size_t N, typename T>
void Fill(A (&array)[N], const T &val)  //多次元初期化
{
  std::fill((T *)array, (T *)(array + N), val);
}
template <class T>
bool chmax(T &a, const T &b)  //最大値更新 返り値はbool
{
  if (a < b) {
    a = b;
    return 1;
  }
  return 0;
}
template <class T>
bool chmin(T &a, const T &b)  //最小値更新 返り値はbool
{
  if (b < a) {
    a = b;
    return 1;
  }
  return 0;
}
int dx[4] = {1, 0, -1, 0};
int dy[4] = {0, 1, 0, -1};
constexpr int INF = 0x3f3f3f3f;
constexpr int LINF = 0x3f3f3f3f3f3f3f3fLL;
constexpr int mod1 = 1e9 + 7;
constexpr int mod2 = 998244353;
//} END

using ld = long double;
using P = complex<ld>;
using G = vector<P>;
const ld pi = acos(-1);
const ld eps = 1e-10;
const ld inf = 1e12;

ld cross(const P &a, const P &b) {
  return a.real() * b.imag() - a.imag() * b.real();
}
ld dot(const P &a, const P &b) {
  return a.real() * b.real() + a.imag() * b.imag();
}

template <class iter>
std::pair<P, ld> min_ball(iter left, iter right, int seed = 1333) {
  const int n = right - left;

  assert(n >= 1);
  if (n == 1) {
    return {*left, ld(0)};
  }

  std::mt19937 mt(seed);
  std::shuffle(left, right, mt);
  // std::random_shuffle(left, right); // simple but deprecated

  iter ps = left;
  using circle = std::pair<P, ld>;

  auto make_circle_3 = [](const P &a, const P &b, const P &c) -> circle {
    ld A = std::norm(b - c), B = std::norm(c - a), C = std::norm(a - b),
       S = cross(b - a, c - a);
    P p = (A * (B + C - A) * a + B * (C + A - B) * b + C * (A + B - C) * c) /
          (4 * S * S);
    ld r2 = std::norm(p - a);
    return {p, r2};
  };

  auto make_circle_2 = [](const P &a, const P &b) -> circle {
    P c = (a + b) / (ld)2;
    ld r2 = std::norm(a - c);
    return {c, r2};
  };

  auto in_circle = [](const P &a, const circle &c) -> bool {
    return std::norm(a - c.first) <= c.second + eps;
  };

  circle c = make_circle_2(ps[0], ps[1]);

  // MiniDisc
  for (int i = 2; i < n; ++i) {
    if (!in_circle(ps[i], c)) {
      // MiniDiscWithPoint
      c = make_circle_2(ps[0], ps[i]);
      for (int j = 1; j < i; ++j) {
        if (!in_circle(ps[j], c)) {
          // MiniDiscWith2Points
          c = make_circle_2(ps[i], ps[j]);
          for (int k = 0; k < j; ++k) {
            if (!in_circle(ps[k], c)) {
              c = make_circle_3(ps[i], ps[j], ps[k]);
            }
          }
        }
      }
    }
  }
  return c;
}

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

  int N;
  cin >> N;

  vector<P> t(N);
  rep(i, 0, N) {
    int x, y;
    cin >> x >> y;
    t[i] = P(x, y);
  }

  pair<P, ld> res = min_ball(t.begin(), t.end());

  cout << Fixed(10) << sqrt(res.second) << '\n';
  return 0;
}

Measured memory_bytes: 512