/*
confirm 0LL and 1LL
confirm cornercases such as 0
confirm times of cin < 10^6
*/
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using P = pair<ll, ll>;
using Vec = vector<ll>;
using VecP = vector<P>;
using VecB = vector<bool>;
using VecC = vector<char>;
using VecD = vector<double>;
using VecS = vector<string>;
using VecVec = vector<Vec>;
using Tree = vector<VecP>;
template <typename T>
using Vec1 = vector<T>;
template <typename T>
using Vec2 = vector<vector<T> >;
#define REP(i, m, n) for(ll (i) = (m); (i) < (n); ++(i))
#define REPN(i, m, n) for(ll (i) = (m); (i) <= (n); ++(i))
#define REPR(i, m, n) for(ll (i) = (m)-1; (i) >= (n); --(i))
#define REPNR(i, m, n) for(ll (i) = (m); (i) >= (n); --(i))
#define rep(i, n) REP(i, 0, n)
#define repn(i, n) REPN(i, 1, n)
#define repr(i, n) REPR(i, n, 0)
#define repnr(i, n) REPNR(i, n, 1)
#define all(s) (s).begin(), (s).end()
#define pb push_back
#define mp make_pair
#define mt make_tuple
#define fs first
#define sc second
template <typename T>
bool chmax(T &a, const T& b){if(a < b){a = b; return true;} return false;}
template <typename T>
bool chmin(T &a, const T& b){if(a > b){a = b; return true;} return false;}
template <typename T>
void co(const T n){cout << n << endl;}
template <typename T>
void cosp(const T n){cout << n << ' ';}
void coVec(const Vec &v){for(ll i : v) cosp(i); cout << endl;}
void sonic(){ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);}
void setp(const ll n){cout << fixed << setprecision(n);}
const ll INF = 1e9+1;
const ll LINF = 1e18+1;
const ll MOD = 1e9+7;
//const ll MOD = 998244353;
const double PI = acos(-1);
const ld EPS = 1e-9;
pair<double, double> calcCircleOf2Point(double x1, double y1, double x2, double y2, double x3, double y3){
	double 	ox, oy, a, b, c, d , cx, cy, r;
	double 	r1, r2, r3 ;
	int stat;

	a = x2 - x1 ;
	b = y2 - y1 ;
	c = x3 - x1 ;
	d = y3 - y1 ;

	stat = -1 ;

	if  ((a && d) || (b && c)) {
		ox = x1 + (d * (a * a + b * b) - b * (c * c + d * d)) / (a * d - b * c) / 2 ;
		if  (b) {
			oy = (a * (x1 + x2 - ox - ox) + b * (y1 + y2)) / b / 2 ;
		} else {
			oy = (c * (x1 + x3 - ox - ox) + d * (y1 + y3)) / d / 2 ;
		}
		r1   = sqrt((ox - x1) * (ox - x1) + (oy - y1) * (oy - y1)) ;
		r2   = sqrt((ox - x2) * (ox - x2) + (oy - y2) * (oy - y2)) ;
		r3   = sqrt((ox - x3) * (ox - x3) + (oy - y3) * (oy - y3)) ;
		cx = ox ;
		cy = oy ;
		r  = (r1 + r2 + r3) / 3 ;
		stat = 0 ;
	}

	return {cx, cy};
}

ld dist(ld x1, ld y1, ld x2, ld y2){
	return sqrt(pow(x1-x2, 2)+pow(y1-y2, 2));
}

int main(void){
	ll n;
	cin >> n;
	VecD x(n), y(n);
	rep(i, n){
		cin >> x[i] >> y[i];
	}

	if(n == 2){
		ld d = dist(x[0], y[0], x[1], y[1]);
		setp(10);
		co(d/2);
		return 0;
	}

	ld ans = INF;
	rep(i, n-1){
		REP(j, i+1, n){
			ld ox = (x[i]+x[j])/2, oy = (y[i]+y[j])/2;
			ld r = dist(x[i], y[i], x[j], y[j]);
			bool flg = true;
			rep(k, n) if(dist(x[k], y[k], ox, oy) > r/2+EPS){
				flg = false;
				break;
			}
			if(flg) chmin(ans, r/2);
		}
	}

	rep(i, n-2){
		REP(j, i+1, n-1){
			REP(k, j+1, n){
				pair<double, double> o = calcCircleOf2Point(x[i], y[i], x[j], y[j], x[k], y[k]);
				ld ox = o.fs, oy = o.sc;
				ld r = dist(x[i], y[i], ox, oy);
				bool flg = true;
				rep(l, n){
					ld d = dist(x[l], y[l], ox, oy);
					if(d > r+EPS){
						flg = false;
						break;
					}
				}
				if(flg) chmin(ans, r);
			}
		}
	}
	setp(10);
	co(ans);

	return 0;
}


Measured memory_bytes: 256