#include <bits/stdc++.h>
//#include <atcoder/modint>

using namespace std;
//using namespace atcoder;
using ll = long long;
using ld = long double;
//using mint = modint998244353;

int main(){
    cin.tie(nullptr);
    ios_base::sync_with_stdio(false);

    int N;
    cin >> N;
    ld gx, gy, mx1=0, mx2=0;
    vector<ld> x(N), y(N);

    gx = 0; gy = 0;
    for (int i=0; i<N; i++){
        cin >> x[i] >> y[i];
        gx += x[i];
        gy += y[i];
    }
    gx /= N;
    gy /= N;
    for (int i=0; i<N; i++){
        mx1 = max(mx1, (x[i]-gx)*(x[i]-gx)+(y[i]-gy)*(y[i]-gy));
    }
    gx = 0; gy = 0;
    for (int i=0; i<N; i++){
        cin >> x[i] >> y[i];
        gx += x[i];
        gy += y[i];
    }
    gx /= N;
    gy /= N;
    for (int i=0; i<N; i++){
        mx2 = max(mx2, (x[i]-gx)*(x[i]-gx)+(y[i]-gy)*(y[i]-gy));
    }

    cout << setprecision(18) << sqrt(mx2/mx1) << endl;

    return 0;
}