#include <bits/stdc++.h>
 
//#include <unistd.h>
//#include <iostream>
 
using namespace std;
 
#define DEBUG(x) cerr<<#x<<": "<<x<<endl;
#define DEBUG_VEC(v) cerr<<#v<<":";for(int i=0;i<v.size();i++) cerr<<" "<<v[i]; cerr<<endl;
#define DEBUG_MAT(v) cerr<<#v<<endl;for(int i=0;i<v.size();i++){for(int j=0;j<v[i].size();j++) {cerr<<v[i][j]<<" ";}cerr<<endl;}
typedef long long ll;
//#define int ll
 
#define vi vector<int>
#define vl vector<ll>
#define vii vector< vector<int> >
#define vll vector< vector<ll> >
#define vs vector<string>
#define pii pair<int,int>
#define pis pair<int,string>
#define psi pair<string,int>
#define pll pair<ll,ll>
template<class S, class T> pair<S, T> operator+(const pair<S, T> &s, const pair<S, T> &t) { return pair<S, T>(s.first + t.first, s.second + t.second); }
template<class S, class T> pair<S, T> operator-(const pair<S, T> &s, const pair<S, T> &t) { return pair<S, T>(s.first - t.first, s.second - t.second); }
template<class S, class T> ostream& operator<<(ostream& os, pair<S, T> p) { os << "(" << p.first << ", " << p.second << ")"; return os; }
#define X first
#define Y second
#define rep(i,n) for(int i=0;i<(n);i++)
#define rep1(i,n) for(int i=1;i<=(n);i++)
#define rrep(i,n) for(int i=(n)-1;i>=0;i--)
#define rrep1(i,n) for(int i=(n);i>0;i--)
#define REP(i,a,b) for(int i=a;i<b;i++)
#define in(x, a, b) (a <= x && x < b)
#define all(c) c.begin(),c.end()
template<class T> bool chmax(T &a, const T &b) { if (a<b) { a = b; return 1; } return 0; }
template<class T> bool chmin(T &a, const T &b) { if (a>b) { a = b; return 1; } return 0; }
#define UNIQUE(v) v.erase(std::unique(v.begin(), v.end()), v.end());
const ll inf = 1000000001;
const ll INF = (ll)1e18 + 1;
const long double pi = 3.1415926535897932384626433832795028841971L;
#define Sp(p) cout<<setprecision(25)<< fixed<<p<<endl;
int dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1};
int dx2[8] = { 1,1,0,-1,-1,-1,0,1 }, dy2[8] = { 0,1,1,1,0,-1,-1,-1 };
#define fio() cin.tie(0); ios::sync_with_stdio(false);
const ll MOD = 1000000007;
//const ll MOD = 998244353;
// #define mp make_pair
//#define endl '\n'


int n;
vector<pii> xy;

double f(pair<double, double> m) {
  double r = 0;
  double x = m.first, y = m.second;
  rep (i, n) {
    double x2 = xy[i].first, y2 = xy[i].second;
    double dist = (x2 - x) * (x2 - x) + (y2 - y) * (y2 - y);
    chmax(r, sqrt(dist));
  }
  return r;
}

double solve(pii xy1, pii xy2) {
  pair<double, double> mid;
  mid.first = (xy1.first + xy2.first) / 2.0;
  mid.second = (xy1.second + xy2.second) / 2.0;

  //DEBUG(mid);
  double ddx = xy2.first - xy1.first;
  double ddy = xy2.second - xy1.second;
  double dx = -ddy, dy = ddx;
  //DEBUG(dx);
  //DEBUG(dy);

  double t1 = -10000, t2 = 10000;
  pair<double, double> xy3, xy4;
  rep (_, 200) {
    double x1 = (2 * t1 + t2) / 3.0;
    double x2 = (t1 + 2 * t2) / 3.0;

    xy3.first = mid.first + dx * x1;
    xy4.first = mid.first + dx * x2;
    xy3.second = mid.second + dy * x1;
    xy4.second = mid.second + dy * x2;
    double f1 = f(xy3), f2 = f(xy4);
    //DEBUG(f1); 
    //DEBUG(f2);
    if (f1 < f2) {
      t2 = x2;
    }
    else {
      t1 = x1;
    }
  }
  return f(xy3);
}

signed main() {
  fio();
  cin >> n;
  xy.resize(n);
  rep (i, n) {
    cin >> xy[i].first >> xy[i].second;
  }

  double ans = inf;
  rep (i, n) {
    for (int j = i + 1; j < n; j++) {
      chmin(ans, solve(xy[i], xy[j]));
    }
  }
  Sp(ans);
}

Measured memory_bytes: 256