#include <bits/stdc++.h>
//#define DEBUG 1106
#define int long long
#define ll long long
#define ld long double
#define pb emplace_back
#define p_q priority_queue
#define m_p make_pair
#define pii pair<int,int>
#define endl '\n'
#define INIT ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define FOR(i,a,b) for(int i = a; i <= b; i++)
#define forn(i,n) for (int i = 0; i < n; i++)
#define forn1(i,n) for (int i = 1; i <= n; i++)
#define all(x) x.begin(),x.end()
#define ft first
#define sd second
#define lowbit(x) (x&(-x))
#define chmax(x,y) x=max(x,y)
#define chmin(x,y) x=min(x,y)
#ifdef DEBUG
#define debug(x) cout << #x << ": " << x << endl;
#else
#define debug(x) 1106;
#endif
using namespace std;
const int N = 1e6+5;
const int M = 2005;
const int inf = 1e9;
const int INF = 1e18;
const int MOD = 1e9+7;
int p[N];
vector<tuple<ld, int, int>> edge;
vector<tuple<int, int, int>> pt;
int getp(int x) {
if(x!=p[x]) p[x] = getp(p[x]);
return p[x];
}
bool merge(int x, int y) {
if(getp(x)==getp(y)) return 0;
p[getp(x)]=getp(y);
return 1;
}
ld dis(ld a, ld b, ld c, ld d) {
return sqrt((a - c)*(a - c) + (b - d)*(b - d));
}
signed main() {
INIT
#ifdef DEBUG
freopen("input.txt", "r", stdin);
#endif
///////////
int n;
cin >> n;
forn1(i,n) p[i]=i;
forn1(i,n) {
int x, y;
cin >> x >> y;
pt.pb(x, y, i);
}
forn(i,n) {
forn(j,n) {
auto [a, b, x] = pt[i];
auto [c, d, y] = pt[j];
edge.pb(dis(a,b,c,d), x, y);
}
}
sort(all(edge));
ld ans = 0.0;
int c = 0;
for (auto[w, u, v]: edge) {
if(merge(u, v)) {
chmax(ans, w);
c++;
}
if(c==n-1) break;
}
cout << fixed << setprecision(9) << ans/2.0;
}
