#include<bits/stdc++.h>
#define f0r(i,n) for(int i = 0; i<n; i++)
#define pb push_back
#define vi vector<long long int>
#define ll long long int
#define mp make_pair
#define pii pair<ll,ll>
#define FOR(i, k, n) for(int i = k; i<n; i++)
using namespace std;
ll dist(pii a, pii b){
return (a.first - b.first) * (a.first - b.first) + (a.second - b.second) * (a.second - b.second);
}
int main(){
int n;
cin>>n;
vector<pair<ll,ll>>pts;
f0r(i,n){
ll a,b;
cin>>a>>b;
pts.pb(mp(a,b));
}
ll lo = 0;
ll hi = 4e18;
while(lo < hi){
ll mid = (lo + hi) / 2;
vector<vi>adj(n);
f0r(i,n){
f0r(j,n){
if(i != j){
if(dist(pts[i], pts[j]) <= mid){
adj[i].pb(j);
adj[j].pb(i);
}
}
}
}
vector<bool>vis(n);
queue<int>q;
q.push(0);
vis[0] = 1;
while(!q.empty()){
int node = q.front();
q.pop();
for(auto u : adj[node]){
if(vis[u])continue;
vis[u] = 1;
q.push(u);
}
}
bool ok = 1;
f0r(i,n)if(!vis[i])ok = 0;
if(ok){
hi = mid;
}
else{
lo = mid + 1;
}
}
cout<<fixed;
cout<<setprecision(17);
cout<<sqrt(lo)/2.0<<'\n';
}
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