#define _USE_MATH_DEFINES

#include <iostream>
#include <cstdio>
#include <string>
#include <cstdlib>
#include <set>
#include <utility>
#include <vector>
#include <list>
#include <algorithm>
#include <regex>
#include <cmath>
#include <map>
#include <iterator>
#include <climits>
#include <numeric>
#include <bitset>
#include <unordered_map>
#include <unordered_set>
#include <iomanip>
#include <queue>
#include <deque>
#include <stack>
#include <array>
#include <valarray>
#include <complex>
#include <random>
#include <functional>
#include <cassert>
#include <chrono>
#include <memory>

using namespace std;

//#define int long long
//region TEMPLATE
#define double long double
typedef long long ll;
typedef unsigned long long ull;

template<typename T>
void __read(T &a) { cin >> a; }

template<typename T, typename ... Args>
void __read(T &a, Args &... args) {
    cin >> a;
    __read(args...);
}

#define make(t, ...) t __VA_ARGS__; __read(__VA_ARGS__)
#define makev(a, n) VI a(n); FOR(n) cin >> a[i];
#define ALL(x) (x).begin(), (x).end()
#define RALL(x) (x).rbegin(), (x).rend()
#define FORIT(p) for(auto it = p.begin(); it != p.end(); it++)
#define FOR(b) for(signed i = 0; i <(b); i++)
#define FORE(i, l, r) for(int i = (l); i < (r); i++)
#define NFOR(i, n) for(int i = (((int) n)-1); i >= 0; i--)
typedef vector<int> VI;
typedef vector<vector<int>> VVI;
typedef pair<int, int> PII;
typedef pair<pair<int, int>, int> PPII;
constexpr ll M7 = 1000000007ll;
constexpr ll M9 = 1000000009ll;
constexpr ll MFFT = 998244353ll;
template<class T>
void outv(T &a) { for (auto &x : a) cout << x << ' '; }
static mt19937 rnd(static_cast<unsigned>(chrono::steady_clock::now().time_since_epoch().count())); // NOLINT(cert-err58-cpp)
template<class T>
static auto __super_speed__ = (ios_base::sync_with_stdio(0), cin.tie(
        0)); // NOLINT(cert-err58-cpp,cppcoreguidelines-interfaces-global-init)
//endregion

const double EPS = 1e-9;

struct point{
    double x, y;
    point(double x = 0, double y = 0) : x(x), y(y) {}
};

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

double cross(point a, point b){
    return a.x * b.y - a.y * b.x;
}

bool is_line(point p1, point p2, point p3){
    point a(p2.x - p1.x, p2.y - p1.y);
    point b(p3.x - p1.x, p3.y - p1.y);
    return abs(cross(a, b)) <= EPS;
}

void mid_normal(point p1, point p2, double& a, double& b, double& c){
    a = p2.x - p1.x;
    b = p2.y - p1.y;
    double xm = (p1.x + p2.x) / 2;
    double ym = (p1.y + p2.y) / 2;
    c = a * xm + b * ym;
}

point intersect_line(double a1, double b1, double c1, double a2, double b2, double c2){
    double d = cross({a1, b1}, {a2, b2});
    double dx = cross({c1, b1}, {c2, b2});
    double dy = cross({a1, c1}, {a2, c2});
    return {dx / d, dy / d};
}


int32_t main() {
    make(int, n);
    vector<point> p(n);
    for(int i = 0; i < n; ++i){
        cin >> p[i].x >> p[i].y;
    }
    auto check = [&p](double x, double y, double r){
        bool ok = true;
        for(int i = 0; ok && i < p.size(); ++i){
            ok = sqr(p[i].x - x) + sqr(p[i].y - y) <= sqr(r) + EPS;
        }
        return ok;
    };
    for(int i = 0; i < n; ++i){
        for(int j = i + 1; j < n; ++j){
            double x = (p[i].x + p[j].x) / 2;
            double y = (p[i].y + p[j].y) / 2;
            double r = hypotl(p[i].x - p[j].x, p[i].y - p[j].y) / 2;
            if (check(x, y, r)){
                cout << fixed << setprecision(10) << r;
                return 0;
            }
        }
    }
    double ans = 2000;
    for(int i = 0; i < n; ++i){
        for(int j = i + 1; j < n; ++j){
            for(int k = j + 1; k < n; ++k){
                if (is_line(p[i], p[j], p[k])){
                    continue;
                }
                double a1, b1, c1, a2, b2, c2;
                mid_normal(p[i], p[j], a1, b1, c1);
                mid_normal(p[i], p[k], a2, b2, c2);
                point c = intersect_line(a1, b1, c1, a2, b2, c2);
                double r = hypotl(c.x - p[i].x, c.y - p[i].y);
                if (check(c.x, c.y, r)){
                    ans = min(ans, r);
                }
            }
        }
    }
    cout << fixed << setprecision(10) << ans;
    return 0;
}

Measured memory_bytes: 512