#include <cmath>

#include <cstdio>

#include <cstring>

#include <algorithm>

#define N 1010

#define squ(x) ((x) * (x))

using namespace std;

const double pi = acos(-1);

struct data

{

    double pl , pr;

    bool operator<(const data &a)const {return pl < a.pl;}

}a[N << 1];

double x[N] , y[N] , r[N];

int tot;

int main()

{

    int n , i , j;

    double afa , beta , d , last , ans = 0;

    scanf("%d" , &n);

    for(i = 1 ; i <= n ; i ++ ) scanf("%lf%lf%lf" , &r[i] , &x[i] , &y[i]);

    for(i = 1 ; i <= n ; i ++ )

    {

        ans += 2 * pi * r[i];

        tot = 0;

        for(j = i + 1 ; j <= n ; j ++ )

        {

            tot ++ , d = squ(x[i] - x[j]) + squ(y[i] - y[j]);

            if(squ(r[i] + r[j]) <= d) a[tot].pl = a[tot].pr = 0;

            else if(squ(r[i] - r[j]) >= d)

            {

                if(r[i] > r[j]) a[tot].pl = a[tot].pr = 0;

                else a[tot].pl = 0 , a[tot].pr = 2 * pi;

            }

            else

            {

                afa = acos((r[i] * r[i] + d - r[j] * r[j]) / (2 * r[i] * sqrt(d)));

                beta = atan2(y[j] - y[i] , x[j] - x[i]);

                if(beta < 0) beta += 2 * pi;

                a[tot].pl = beta - afa , a[tot].pr = beta + afa;

                if(a[tot].pl < 0) tot ++ , a[tot].pl = a[tot - 1].pl + 2 * pi , a[tot - 1].pl = 0 , a[tot].pr = 2 * pi;

                else if(a[tot].pr > 2 * pi) tot ++ , a[tot].pr = a[tot - 1].pr - 2 * pi , a[tot - 1].pr = 2 * pi , a[tot].pl = 0;

            }

        }

        sort(a + 1 , a + tot + 1);

        last = -1;

        for(j = 1 ; j <= tot ; j ++ )

        {

            if(a[j].pr <= last) continue;

            if(a[j].pl > last) ans -= (a[j].pr - a[j].pl) * r[i];

            else ans -= (a[j].pr - last) * r[i];

            last = a[j].pr;

        }

    }

    printf("%.3lf\n" , ans);

    return 0;

}