// >>> TEMPLATES
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
#define int ll
#define double ld
#define rep(i,n) for (int i = 0; i < (int)(n); i++)
#define rep1(i,n) for (int i = 1; i <= (int)(n); i++)
#define repR(i,n) for (int i = (int)(n)-1; i >= 0; i--)
#define rep1R(i,n) for (int i = (int)(n); i >= 1; i--)
#define loop(i,a,B) for (int i = a; i B; i++)
#define loopR(i,a,B) for (int i = a; i B; i--)
#define all(x) (x).begin(), (x).end()
#define allR(x) (x).rbegin(), (x).rend()
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define fst first
#define snd second
#define INF (numeric_limits<int>::max()/2-1)
#ifdef LOCAL
#include "debug.hpp"
#define dump(...) cerr << "[" << __LINE__ << ":" << __FUNCTION__ << "] ", dump_impl(#__VA_ARGS__, __VA_ARGS__)
#define say(x) cerr << "[" << __LINE__ << ":" << __FUNCTION__ << "] " << x << endl
#define debug if (1)
#else
#define dump(...) (void)(0)
#define say(x) (void)(0)
#define debug if (0)
#endif
template <class T> using pque_max = priority_queue<T>;
template <class T> using pque_min = priority_queue<T, vector<T>, greater<T> >;
template <class T, class = typename T::iterator, class = typename enable_if<!is_same<T, string>::value>::type>
ostream& operator<<(ostream& os, T const& v) { bool f = true; for (auto const& x : v) os << (f ? "" : " ") << x, f = false; return os; }
template <class T, class = typename T::iterator, class = typename enable_if<!is_same<T, string>::value>::type>
istream& operator>>(istream& is, T &v) { for (auto& x : v) is >> x; return is; }
template <class T, class S> istream& operator>>(istream& is, pair<T,S>& p) { return is >> p.first >> p.second; }
struct IOSetup { IOSetup() { cin.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(15); } } iosetup;
template <class F> struct FixPoint : private F {
    constexpr FixPoint(F&& f) : F(forward<F>(f)) {}
    template <class... T> constexpr auto operator()(T&&... x) const { return F::operator()(*this, forward<T>(x)...); }
};
struct MakeFixPoint {
    template <class F> constexpr auto operator|(F&& f) const { return FixPoint<F>(forward<F>(f)); }
};
#define MFP MakeFixPoint()|
#define def(name, ...) auto name = MFP [&](auto &&name, __VA_ARGS__)
template <class T, size_t d> struct vec_impl {
    using type = vector<typename vec_impl<T,d-1>::type>;
    template <class... U> static type make_v(size_t n, U&&... x) { return type(n, vec_impl<T,d-1>::make_v(forward<U>(x)...)); }
};
template <class T> struct vec_impl<T,0> { using type = T; static type make_v(T const& x = {}) { return x; } };
template <class T, size_t d = 1> using vec = typename vec_impl<T,d>::type;
template <class T, size_t d = 1, class... Args> auto make_v(Args&&... args) { return vec_impl<T,d>::make_v(forward<Args>(args)...); }
template <class T> void quit(T const& x) { cout << x << endl; exit(0); }
template <class T> constexpr bool chmin(T& x, T const& y) { if (x > y) { x = y; return true; } return false; }
template <class T> constexpr bool chmax(T& x, T const& y) { if (x < y) { x = y; return true; } return false; }
template <class It> constexpr auto sumof(It b, It e) { return accumulate(b,e,typename iterator_traits<It>::value_type{}); }
template <class T> int sz(T const& x) { return x.size(); }
// <<<

double sq(double x) { return x*x; }
const double eps = 1e-6;

int32_t main() {
    int n; cin >> n;
    vector<double> x(n),y(n);
    rep (i,n) cin >> x[i] >> y[i];


    auto f = [&](int i, int j, int k) -> tuple<double,double,double> {
        double aa = sq(x[j]-x[k]) + sq(y[j]-y[k]);
        double bb = sq(x[k]-x[i]) + sq(y[k]-y[i]);
        double cc = sq(x[i]-x[j]) + sq(y[i]-y[j]);
        tuple<double,double,double> xxx(0,0,-1);
        if (abs( sqrt(aa)+sqrt(bb)-sqrt(cc) ) < eps) return xxx;
        if (abs( sqrt(bb)+sqrt(cc)-sqrt(aa) ) < eps) return xxx;
        if (abs( sqrt(cc)+sqrt(aa)-sqrt(bb) ) < eps) return xxx;

        double A = aa*(bb+cc-aa);
        double B = bb*(cc+aa-bb);
        double C = cc*(aa+bb-cc);
        double x0 = (A*x[i] + B*x[j] + C*x[k])/(A+B+C);
        double y0 = (A*y[i] + B*y[j] + C*y[k])/(A+B+C);
        double ri = sqrt(sq(x[i]-x0) + sq(y[i]-y0));
        double rj = sqrt(sq(x[j]-x0) + sq(y[j]-y0));
        double rk = sqrt(sq(x[k]-x0) + sq(y[k]-y0));
        // dump(aa,bb,cc);
        // dump(A,B,C);
        // dump(x0,y0);
        // dump(ri,rj,rk);
        assert( abs(ri-rj) < eps );
        assert( abs(ri-rk) < eps );
        return tuple<double,double,double>(x0,y0,ri);
    };

    double mi = INF;

    rep (i,n) rep (j,n) if (i < j) {
        double x0 = (x[i]+x[j])/2;
        double y0 = (y[i]+y[j])/2;
        double r  = sqrt(sq(x[i]-x[j]) + sq(y[i]-y[j])) /2;

                if (r < 0 || mi < r) continue;
        bool flag = false;
        rep (s,n) {
            double dx = x[s]-x0;
            double dy = y[s]-y0;
            if (dx*dx + dy*dy > r*r + 1e-10) flag = true;
        }
        if (!flag) chmin(mi,r);


    }


    rep (i,n) rep (j,n) rep (k,n) if (i < j && j < k) {
        double x0,y0,r; tie(x0,y0,r) = f(i,j,k);
        if (r < 0 || mi < r) continue;
        bool flag = false;
        rep (s,n) {
            double dx = x[s]-x0;
            double dy = y[s]-y0;
            if (dx*dx + dy*dy > r*r + 1e-10) flag = true;
        }
        if (!flag) chmin(mi,r);
    }

    cout << mi << endl;
}


Measured memory_bytes: 256