/*****************************************
备注：
******************************************/
#include <queue>
#include <math.h>
#include <stack>
#include <stdio.h>
#include <iostream>
#include <vector>
#include <iomanip>
#include <string.h>
#include <algorithm>
using namespace std;
#define LL long long
const int N = 4e6 + 10;
const int INF = 0x3f3f3f3f;
struct node
{
	int x, y;
	double num;
}p[N];
int n , m , a[1000];
double x[N] , y[N];
inline double calc(double x1 , double y1 ,double x2 , double y2)
{
	return sqrt( (x1-x2)*(x1-x2) + (y1-y2)*(y1-y2) );
}
void init()
{
	for(int i = 0; i <= n ; i++)
		a[i] = i;
}
int fa(int x)
{
	if(x == a[x])	return x;
	return a[x] = fa(a[x]);
}
bool cmp(node xx , node yy)
{
	return xx.num < yy.num;
}
int main()
{
	cin >> n >> m;
	init();
	int len = 0;
	for(int i = 1 ; i <= n ; i++)
	{
		cin >> x[i] >> y[i];
		for(int j = 1 ; j < i ; j++)
		{
			p[len].x = i , p[len].y = j;
			p[len++].num = calc(x[i],y[i] , x[j] , y[j]);
		}
	}
	sort(p,p+len,cmp);
	int sum = 0;
	while(m--)
	{
		int xx,yy;
		cin >> xx >> yy;
		xx = fa(xx);
		yy = fa(yy);
		if(xx != yy)
		{
			a[xx] = yy;
			sum++;
		}
	}
	double ans = 0;
	for(int i = 0 ; i < len ; i++)
	{
		int xx = p[i].x , yy = p[i].y;
		xx = fa(xx) , yy = fa(yy);
		if(xx != yy)
		{
			a[xx] = yy;
			sum++;
			ans += p[i].num;
			
		}
		if(sum == n-1)
			break;
	}
	printf("%.2lf\n",ans);
	return 0;
}