#include<bits/stdc++.h>
#define L(i, j, k) for(int i = (j); i <= (k); i++)
#define R(i, j, k) for(int i = (j); i >= (k); i--)
#define ll long long
#define ull unsigned long long 
#define sz(a) ((int) a.size())
#define vi vector<int>
#define me(a, x) memset(a, x, sizeof(a))
using namespace std;
const int N = 1 << 21, L = 5e5, mod = 998244353;

ll MD = 1e18;
mt19937_64 orz;
double randreal(double l, double r) {
	double len = r - l;
	return ((orz() % MD) * len / MD) + l;
}

int n = 3;
double x[N], y[N];

inline double calc(double x, double y) {
	double sum = 0;
	L(i, 1, 3) 
		sum += i * sqrt((::x[i] - x) * (::x[i] - x) + (::y[i] - y) * (::y[i] - y));
	return sum;
}

double work() {
	double temp = 1e4;
	double x = randreal(-1e4, 1e4);
	double y = randreal(-1e4, 1e4);
	
	double ans = calc(x, y);
	while(temp > 1e-10) {
		double nx = x + randreal(-temp, temp);
		double ny = y + randreal(-temp, temp);
		double nans = calc(nx, ny);
		if(nans < ans) 
			x = nx, y = ny, ans = nans;
		temp *= 0.997;
	}
	return ans;
}

int main () { 
	ios :: sync_with_stdio(false);
	cin.tie (0); cout.tie (0);
	cout.precision(12); cout << fixed;
	L(i, 1, n) {
		cin >> x[i] >> y[i];
	}
	cout << work() << '\n';
	return 0;
}