#include <iostream>
#include <algorithm>
#include <vector>
#include <cmath>
using namespace std;
const long double PI = acos(-1);
struct cyl {
    long double cx;
    long double cy;
    long double radii;
};

vector<pair<long double,long double>> vec_dup;
void f(cyl cyl1, cyl cyl2){
    auto [cx1,cy1,r1] = cyl1;
    auto [cx2,cy2,r2] = cyl2;
    long double rad_centers = atan2(cy2-cy1,cx2-cx1);
    long double rad_tan = asin((r1+r2)/hypot(cy2-cy1,cx2-cx1));
    long double rad1 = rad_centers - rad_tan - 2*PI;
    for (int i = 0; i < 8; i++){
        vec_dup.push_back({rad1,rad1 + 2*rad_tan});
        rad1 += PI;
    }
}

int main(void){
    ios::sync_with_stdio(0); cin.tie(0);
    cout << fixed;
    cout.precision(12);

    int n; cin >> n;
    vector<cyl> vec(n);
    for (auto &[cx,cy,radii]: vec)
        cin >> cx >> cy >> radii;

    for (int i = 0; i < n; i++){
        for (int j = i+1; j < n; j++){
            f(vec[i], vec[j]);
        }
    }

    long double ans = -1;
    sort(vec_dup.begin(), vec_dup.end());
    long double dup = PI;
    for (auto [rad1,rad2] : vec_dup){
        if (rad1 > dup){
            ans = max(ans, rad1 - dup);
        }
        dup = max(dup, rad2);
    }
    if (ans < 0)
        cout << "0\n";
    else
        cout << ans << "\n";
}