#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define ld long double
#define endl '\n'
ll calc(ll x ,ll y){
return abs(x - y) * abs(x-y);
}
int n;
vector<bool>vis;
vector<vector<ll>>a((1e3) + 5,vector<ll>(int(1e3) + 5));
int cnt =0;
void dfs(int idx,ld mid){
if(vis[idx])
{
return;
}
vis[idx] = 1;
for(int i=0;i<n;i++){
if(i == idx)continue;
if((ld)sqrt(a[idx][i]) > mid)continue;
dfs(i,mid);
}
return;
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
cin >> n;
vis.resize(n);
vector<pair<ll,ll>>v;
for(int i=0;i<n;i++){
ll x,y;cin >> x >> y;
v.push_back({x,y});
}
for(int i=0;i<n;i++){
for(int j=0;j<n;j++){
if(i == j)continue;
a[i][j] = calc(v[i].first,v[j].first) + calc(v[i].second,v[j].second);
}
}
ld l = 0.0000000000;
ld r = 2e18;
ld ans =0.00000000000;
for(int i=0;i<100;i++){
ld mid = (r+l)/2;
vis = vector<bool>(n);
dfs(0,mid);
bool f= false;
for(int j=0;j<n;j++){
if(vis[j] == 0)
{
f = true;
break;
}
}
if(!f){
r = mid;
ans = mid;
}else{
l = mid;
}
}
cout << fixed << setprecision(10) << ans / 2 << endl;
}
