#include <bits/stdc++.h>
#include <boost/multiprecision/cpp_int.hpp>
using namespace std;
using namespace boost::multiprecision;

# define REP(i,n) for (int i=0;i<(n);++i)
# define rep(i,a,b) for(int i=a;i<(b);++i)
# define p(s) std::cout << s ;
# define pl(s)  std::cout << s << endl;
# define all(v) v.begin(),v.end()
# define showVector(v) REP(i,v.size()){p(v[i]);p(" ")} pl("")
template<class T> inline bool chmin(T &a, T b){ if(a > b) { a = b; return true;} return false;}
template<class T> inline bool chmax(T &a, T b){ if(a < b) { a = b; return true;} return false;}
typedef long long int ll;
typedef pair<ll,ll> P_ii;
typedef pair<double,double> P_dd;

template<class T>
vector<T> make_vec(size_t a){
    return vector<T>(a);
}

template<class T, class... Ts>
auto make_vec(size_t a, Ts... ts){
  return vector<decltype(make_vec<T>(ts...))>(a, make_vec<T>(ts...));
}

template<typename T,typename V>
typename enable_if<is_class<T>::value==0>::type
fill_v(T &t,const V &v){t=v;}

template<typename T,typename V>
typename enable_if<is_class<T>::value!=0>::type
fill_v(T &t,const V &v){
  for(auto &e:t) fill_v(e,v);
}

ll gcd(ll a, ll b) {
    if(a < b) swap(a,b);
    
    if(b == 0) return a;
    return gcd(b, a % b);
}

ll lcm(ll a, ll b){
    ll g = gcd(a,b);
    return (a/g)*b;
}

// 素数判定 O(√n)
bool is_prime(int n){
    for(int i = 2; i * i <= n; i++){
        if(n % i == 0) return false;
    }
    return true;
}

// 約数列挙 O(√n)
vector<ll> divisor(ll n){
    vector<ll> res;
    for(ll i = 1; i * i <= n; i++){
        if(n % i == 0){
            res.push_back(i);
            if(i != n / i) res.push_back(n / i);
        }
    }
    return res;
}

vector<pair<ll, ll> > prime_factorize(ll n) {
    vector<pair<ll, ll> > res;
    for (ll p = 2; p * p <= n; ++p) {
        if (n % p != 0) continue;
        ll num = 0;
        while (n % p == 0) { ++num; n /= p; }
        res.push_back(make_pair(p, num));
    }
    if (n != 1) res.push_back(make_pair(n, 1));
    return res;
}

// auto mod int
// https://youtu.be/L8grWxBlIZ4?t=9858
// https://youtu.be/ERZuLAxZffQ?t=4807 : optimize
// https://youtu.be/8uowVvQ_-Mo?t=1329 : division
const int mod = 1000000007;
struct mint {
  ll x; // typedef long long ll;
  mint(ll x=0):x(x%mod){}
  mint& operator+=(const mint a) {
    if ((x += a.x) >= mod) x -= mod;
    return *this;
  }
  mint& operator-=(const mint a) {
    if ((x += mod-a.x) >= mod) x -= mod;
    return *this;
  }
  mint& operator*=(const mint a) {
    (x *= a.x) %= mod;
    return *this;
  }
  mint operator+(const mint a) const {
    mint res(*this);
    return res+=a;
  }
  mint operator-(const mint a) const {
    mint res(*this);
    return res-=a;
  }
  mint operator*(const mint a) const {
    mint res(*this);
    return res*=a;
  }
  mint pow(ll t) const {
    if (!t) return 1;
    mint a = pow(t>>1);
    a *= a;
    if (t&1) a *= *this;
    return a;
  }
 
  // for prime mod
  mint inv() const {
    return pow(mod-2);
  }
  mint& operator/=(const mint a) {
    return (*this) *= a.inv();
  }
  mint operator/(const mint a) const {
    mint res(*this);
    return res/=a;
  }
};

const int MOD = 1000000007;
const int inf=1e9+7;
const ll longinf=1LL<<60 ;

void addM(ll &a, ll b) {
    a += b;
    if (a >= MOD) a -= MOD;
}

void mulM(ll &a, ll b) {
    a = ((a%MOD)*(b%MOD))%MOD ;
}

ll powM(ll a,ll b) {
    ll ret = 1;
    ll tmp = a;
    while(b>0) {
        if((b&1)==1) ret = (ret * tmp) % MOD;
        tmp = (tmp * tmp) % MOD;
        b = b >> 1;
    }
    return ret;
}

// mod. m での a の逆元 a^{-1} を計算する
ll modinv(ll a, ll m) {
    ll b = m, u = 1, v = 0;
    while (b) {
        ll t = a / b;
        a -= t * b; swap(a, b);
        u -= t * v; swap(u, v);
    }
    u %= m;
    if (u < 0) u += m;
    return u;
}

/* 
最小包含円
https://tubo28.me/compprog/algorithm/minball/
<使い方>
両端のポインタかイテレータ (半開区間) を渡す．
中心の座標と半径 の2乗 のペア返す．
入力の区間をシャッフルする．
第3引数には std::shuffle が使う乱数生成器のシードを指定する．
ハックがあるコンテストでは time(0) や random_device()() を渡したほうが良い
*/

using ld = long double;
const ld eps = 1e-10;
using P = complex<ld>;

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;
}

int main(void) {
  cin.tie(0);
  ios::sync_with_stdio(false);  

  int N;
  cin >> N;
  vector<P> ps(N);
  REP(i, N) {
    double x, y;
    cin >> x >> y;
    ps[i] = P(x, y);
  }

  auto mb = min_ball(begin(ps), end(ps));
  cout << fixed << setprecision(10) << sqrt(mb.second) << endl;

  return 0; 
}

Measured memory_bytes: 256