#include<bits/stdc++.h>
//ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef unsigned int ui;
typedef pair<int,int> pii;
typedef pair<pii,int> ppii;
typedef pair<int,pii> pipi;
typedef pair<ll,ll> pll;
typedef pair<pll,ll> ppll;
typedef pair<ll,pll> plpl;
typedef tuple<ll,ll,ll> tl;
ll mod=1000000007;
ll mod2=998244353;
ll mod3=1000003;
ll mod4=998244853;
ll inf=1000000000000000000;
long double pi=3.14159265358979323846L;
double eps=1e-12;
#define rep(i,m,n) for(ll i=m;i<n;i++)
#define rrep(i,n,m) for(ll i=n;i>=m;i--)
int dh[4]={1,-1,0,0};
int dw[4]={0,0,1,-1};
int ddh[8]={-1,-1,-1,0,0,1,1,1};
int ddw[8]={-1,0,1,-1,1,-1,0,1};
ll lmax(ll a,ll b){
    if(a<b)return b;
    else return a;
}
ll lmin(ll a,ll b){
    if(a<b)return a;
    else return b;
}
ll gcd(ll a,ll b){
    if(a<b)swap(a,b);
    if(b==0)return a;
    if(a%b==0)return b;
    return gcd(b,a%b);
}
ll Pow(ll n,ll k){
    ll ret=1;
    ll now=n;
    while(k>0){
        if(k&1)ret*=now;
        now*=now;
        k/=2;
    }
    return ret;
}
ll gya[1000010];
ll kai[1000010];
ll beki(ll n,ll k,ll md){
  ll ret=1;
  ll now=n;
  while(k>0){
    if(k%2==1){
      ret*=now;
      ret%=md;
    }
    now*=now;
    now%=md;
    k/=2;
  }
  return ret;
}
ll gyaku(ll n,ll md){
  return beki(n,md-2,md);
}
void nckinit(ll n,ll md){
  kai[0]=1;
  kai[1]=1;
  for(int i=2;i<=n;i++){
    kai[i]=kai[i-1]*i;
    kai[i]%=md;
  }
  gya[n]=gyaku(kai[n],md);
  for(int i=n-1;i>=1;i--){
    gya[i]=gya[i+1]*(i+1);
    gya[i]%=md;
  }
  gya[0]=1;
}
ll nck(ll n,ll k,ll md){
  if(k<0)return 0;
  if(k==0||n==k)return 1;
  ll ret=kai[n];
  ret*=gya[n-k];
  ret%=md;
  ret*=gya[k];
  ret%=md;
  return ret;
}
ll npk(ll n,ll k,ll md){
  if(k<0)return 0;
  if(k==0)return 1;
  ll ret=kai[n];
  ret*=gya[n-k];
  ret%=md;
  return ret;
}
pair<double,double> ff(double a,double b,double c,double d,double e,double f){
    if(abs(b*d-a*e)<=eps)return {1000000000000,1000000000000};
    double rx=(c*e-b*f)/(b*d-a*e);
    double ry=(a*f-c*d)/(b*d-a*e);
    return {rx,ry};
}
pair<double,double> g(double a,double b,double c,double d,double e,double f){
    return ff(a-c,b-d,-(b*b-d*d)/2.0-(a*a-c*c)/2.0,c-e,d-f,-(d*d-f*f)/2.0-(c*c-e*e)/2.0);
}
double dist(double a,double b,double c,double d){
    return pow(((a-c)*(a-c)+(b-d)*(b-d)),0.5);
}
int main(){
    ios::sync_with_stdio(false);cin.tie(0);
    int n;cin>>n;
    double x[n],y[n];
    rep(i,0,n)cin>>x[i]>>y[i];
    /*if(n==2){
        double d=(x[0]-x[1])*(x[0]-x[1])+(y[0]-y[1])*(y[0]-y[1]);
        d=sqrt(d);
        d/=2.0;
        cout<<fixed<<setprecision(12)<<d<<endl;
        return 0;
    }*/
    double anss=1000000000000;
    rep(i,0,n-2){
        rep(j,i+1,n-1){
            rep(k,j+1,n){
                pair<double,double> ans=g(x[i],y[i],x[j],y[j],x[k],y[k]);
                if(abs(ans.first-1000000000000)<=eps)continue;
                double dis=dist(ans.first,ans.second,x[i],y[i]);
                int yy=0;
                rep(l,0,n){
                    if(dist(x[l],y[l],ans.first,ans.second)>dis+eps){
                        yy=1;
                        break;
                    }
                }
                if(yy==0)anss=min(anss,dis);
            }
        }
    }
    rep(i,0,n-1){
        rep(j,i+1,n){
            pair<double,double> ans={(x[i]+x[j])/2.0,(y[i]+y[j])/2.0};
            double dis=dist(ans.first,ans.second,x[i],y[i]);
            int yy=0;
            rep(l,0,n){
                if(dist(x[l],y[l],ans.first,ans.second)>dis+eps){
                    yy=1;
                    break;
                }
            }
            if(yy==0)anss=min(anss,dis);
        }
    }
    cout<<fixed<<setprecision(12)<<anss<<endl;
}



Measured memory_bytes: 384