#include <iostream>
#include <sstream>
#include <iomanip>
#include <vector>
#include <string>
#include <map>
#include <set>
#include <algorithm>
#include <numeric>
#include <iterator>
#include <functional>
#include <complex>
#include <queue>
#include <stack>
#include <cmath>
#include <cassert>
#include <cstring>
using namespace std;
typedef long long LL;
typedef complex<double> CMP;
class KingdomXCitiesandVillages { public:
double determineLength(vector <int> cityX, vector <int> cityY, vector <int> villageX, vector <int> villageY)
{
const int C = cityX.size();
const int V = villageX.size();
double answer = 0.0;
for(int i=0; i<V; ++i)
{
double nc = 1e+30;
for(int j=0; j<C; ++j)
nc = min(nc, distance(villageX[i], villageY[i], cityX[j], cityY[j]));
vector<double> d;
for(int j=0; j<V; ++j)
if( j != i )
d.push_back( distance(villageX[i], villageY[i], villageX[j], villageY[j]) );
sort(d.begin(), d.end());
double prob = 1.0;
for(int j=0; j<d.size() && d[j]<nc; ++j)
{
double p = 1.0 / (j+1) / (j+2);
answer += p * d[j];
prob -= p;
}
answer += prob * nc;
}
return answer;
}
static double distance(double x, double y, double X, double Y)
{
return hypot(x-X, y-Y);
}
};
// BEGIN CUT HERE
#include <ctime>
double start_time; string timer()
{ ostringstream os; os << " (" << int((clock()-start_time)/CLOCKS_PER_SEC*1000) << " msec)"; return os.str(); }
template<typename T> ostream& operator<<(ostream& os, const vector<T>& v)
{ os << "{ ";
for(typename vector<T>::const_iterator it=v.begin(); it!=v.end(); ++it)
os << '\"' << *it << '\"' << (it+1==v.end() ? "" : ", "); os << " }"; return os; }
void verify_case(const double& Expected, const double& Received) {
bool ok = (abs(Expected - Received) < 1e-9);
if(ok) cerr << "PASSED" << timer() << endl; else { cerr << "FAILED" << timer() << endl;
cerr << "\to: \"" << Expected << '\"' << endl << "\tx: \"" << Received << '\"' << endl; } }
#define CASE(N) {cerr << "Test Case #" << N << "..." << flush; start_time=clock();
#define END verify_case(_, KingdomXCitiesandVillages().determineLength(cityX, cityY, villageX, villageY));}
int main(){
CASE(0)
int cityX_[] = {3};
vector <int> cityX(cityX_, cityX_+sizeof(cityX_)/sizeof(*cityX_));
int cityY_[] = {0};
vector <int> cityY(cityY_, cityY_+sizeof(cityY_)/sizeof(*cityY_));
int villageX_[] = {3,3};
vector <int> villageX(villageX_, villageX_+sizeof(villageX_)/sizeof(*villageX_));
int villageY_[] = {2,1};
vector <int> villageY(villageY_, villageY_+sizeof(villageY_)/sizeof(*villageY_));
double _ = 2.5;
END
CASE(1)
int cityX_[] = {1,4,7,10};
vector <int> cityX(cityX_, cityX_+sizeof(cityX_)/sizeof(*cityX_));
int cityY_[] = {5,5,5,5};
vector <int> cityY(cityY_, cityY_+sizeof(cityY_)/sizeof(*cityY_));
int villageX_[] = {1,4,7,10};
vector <int> villageX(villageX_, villageX_+sizeof(villageX_)/sizeof(*villageX_));
int villageY_[] = {4,4,4,4};
vector <int> villageY(villageY_, villageY_+sizeof(villageY_)/sizeof(*villageY_));
double _ = 4.0;
END
CASE(2)
int cityX_[] = {1,2,3};
vector <int> cityX(cityX_, cityX_+sizeof(cityX_)/sizeof(*cityX_));
int cityY_[] = {4,4,4};
vector <int> cityY(cityY_, cityY_+sizeof(cityY_)/sizeof(*cityY_));
int villageX_[] = {4,5,6};
vector <int> villageX(villageX_, villageX_+sizeof(villageX_)/sizeof(*villageX_));
int villageY_[] = {4,4,4};
vector <int> villageY(villageY_, villageY_+sizeof(villageY_)/sizeof(*villageY_));
double _ = 4.166666666666667;
END
CASE(3)
int cityX_[] = {1};
vector <int> cityX(cityX_, cityX_+sizeof(cityX_)/sizeof(*cityX_));
int cityY_[] = {1};
vector <int> cityY(cityY_, cityY_+sizeof(cityY_)/sizeof(*cityY_));
int villageX_[] = {2};
vector <int> villageX(villageX_, villageX_+sizeof(villageX_)/sizeof(*villageX_));
int villageY_[] = {1};
vector <int> villageY(villageY_, villageY_+sizeof(villageY_)/sizeof(*villageY_));
double _ = 1;
END
/*
CASE(4)
int cityX_[] = ;
vector <int> cityX(cityX_, cityX_+sizeof(cityX_)/sizeof(*cityX_));
int cityY_[] = ;
vector <int> cityY(cityY_, cityY_+sizeof(cityY_)/sizeof(*cityY_));
int villageX_[] = ;
vector <int> villageX(villageX_, villageX_+sizeof(villageX_)/sizeof(*villageX_));
int villageY_[] = ;
vector <int> villageY(villageY_, villageY_+sizeof(villageY_)/sizeof(*villageY_));
double _ = ;
END
*/
}
// END CUT HERE