#include <bits/stdc++.h>
#define rep(i,a,b) for(int i=a;i<=b;i++)
using namespace std;
int n,x[205],y[205];
double dis[205];
double sqr(int x){ return 1.00*x*x; }
int main(){
    cin>>n;
    rep(i,1,n){
        cin>>x[i]>>y[i];
    }
    double ans = 100000;
    rep(i,1,n){
        rep(j,1,n){
            dis[j] = sqrt(sqr(x[j]-x[i])+sqr(y[j]-y[i]));
        }
        sort(dis+1,dis+n+1);
        ans = min(ans,dis[n]+dis[n-1]);
    }
    cout<<fixed<<setprecision(10);
    cout<<ans;
    return 0;
}