#include<bits/stdc++.h>
using namespace std;

#define fastio ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL); 

#define ll long long
#define ff first
#define ss second
#define pb push_back
#define pf push_front
#define mp make_pair
#define pu push
#define pp pop_back
#define in insert
#define ld long double
#define forn(low,high,i) for(i = low;i < high;i++)
#define forrev(high,low,i) for(i = high; i >= low;i--)
#define all(v) v.begin(),v.end()
#define sz(v) (int)v.size()
#define line cout << __LINE__;
#define prv(a) for(auto x : a) cout << x << ' ';cout << '\n';
#define prvp(a) for(auto x : a) cout << "{" << x.ff << ',' << x.ss << "}";cout << '\n';
#define decimal_digits cout << fixed << setprecision(15);
string to_string(string s) { return '"' + s + '"';}
string to_string(char s) { return string(1, s);}
string to_string(const char* s) { return to_string((string) s);}
string to_string(bool b) { return (b ? "true" : "false");}
template <typename A> string to_string(A);
template <typename A, typename B>string to_string(pair<A, B> p) {return "(" + to_string(p.first) + ", " + to_string(p.second) + ")";}
template <typename A> string to_string(A v) {bool f = 1; string r = "{"; for (const auto &x : v) {if (!f)r += ", "; f = 0; r += to_string(x);} return r + "}";}
void debug_out() { cerr << endl; }
template <typename Head, typename... Tail> void debug_out(Head H, Tail... T) {cerr << " " << to_string(H); debug_out(T...);}
#define pr(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)

typedef unordered_map<int,int> umi;
typedef unordered_map<ll,ll> uml;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<vi> vvi;
typedef vector<vl> vvl;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef vector<pii> vpii;
typedef vector<pll> vpll;
typedef pair<ld, ld> pld;

mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());

const int inf = 1e9;
const ll INF = 1e18;
const int mod = 1e9 + 7;
const int bit32 = log2(inf) + 3;
const int bit64 = log2(INF) + 3;
const ld eps = 1e-6;


inline int add(int a, int b){a += b; if(a >= mod) a -= mod; return a;}
inline int sub(int a, int b){a -= b; if(a < 0) a += mod; return a;}
inline int mul(int a, int b){return (int)((long long) a * b % mod);}
inline int modexpo(int a, int b){int res = 1; while(b > 0){ if(b & 1) res = mul(res, a); a = mul(a, a); b /= 2;} return res;}
inline int divide(int a, int b){ return mul(a, modexpo(b, mod - 2));}

clock_t time_p = clock();

void ktj(){
  time_p = clock() - time_p;
  cerr << "Time elapsed : " << (float)(time_p)/CLOCKS_PER_SEC << "\n";
}

void pre(){ // Reset each global variable (esp. for graphs)
  
}

ld Euclid(pld a, pld b){
  return sqrt((a.ff - b.ff)*(a.ff - b.ff) + (a.ss - b.ss)*(a.ss - b.ss));
}

ld cosine(ld a, ld b, ld c){
  ld res = (b*b + c*c - a*a);
  res /= (2*b*c);
  return (ld)acos(res);
}

pair<ld, pld> CC(pld a, pld b, pld c){
  ld R, A, B, C, del;

  A = Euclid(b, c);
  B = Euclid(a, c);
  C = Euclid(a, b);

  del = 0.0;
  del += a.ff * (b.ss - c.ss);
  del += b.ff * (c.ss - a.ss);
  del += c.ff * (a.ss - b.ss);
  del = fabs(del);
  del /= 2.0;

  ld angA = cosine(A, B, C);
  ld angB = cosine(B, A, C);
  ld angC = cosine(C, A, B);

  ld x = 0, y = 0;
  x += a.ff * sin(2*angA);
  x += b.ff * sin(2*angB);
  x += c.ff * sin(2*angC); 

  y += a.ss * sin(2*angA);
  y += b.ss * sin(2*angB);
  y += c.ss * sin(2*angC); 

  ld sum = sin(2*angA) + sin(2*angB) + sin(2*angC);
  x /= sum;
  y /= sum;
  R = (A * B) * (C / (4 * del));
  return {R, {x, y}};
}

vector<pld> pt;

bool check(ld x, ld y, ld R){
  int cnt = 0;
  for(auto p : pt){
    ld d = Euclid(p, {x, y});
    if(R > d){
      cnt++;
    }else if(fabs(R - d) <= eps){
      cnt++;
    }
  }
  if(cnt == (int)pt.size())
    return true;
  return false;
}

void solve(){
  int n, i, j, k;
  cin >> n;
  pt.resize(n);
  forn(0, n, i){
    cin >> pt[i].ff >> pt[i].ss;
  }

  ld ans = inf;

  forn(0, n, i){
    forn(i + 1, n, j){
      forn(j + 1, n, k){
        pld a = pt[i], b = pt[j], c = pt[k];
        auto rr = CC(a, b, c);
        if(check(rr.ss.ff, rr.ss.ss, rr.ff)){
          ans = min(ans, rr.ff);
        }
      }
    }
  }

  forn(0, n, i){
    forn(i + 1, n, j){
      pld a = pt[i], b = pt[j];
      ld x = (a.ff + b.ff) / 2;
      ld y = (a.ss + b.ss) / 2;
      ld R = Euclid(a, b) / 2;
      if(check(x, y, R)){
        ans = min(ans, R);
      }
    }
  }

  decimal_digits;

  cout << ans << '\n';
}

int main(){
  fastio

  pre();

  int t = 1;
  // cin >> t;
  while(t--){
    solve();
  }

  ktj();
}


Measured memory_bytes: 384