#include<iostream>

 #include<cstdio>

 #include<cstring>

 #include<cmath>

 #include<queue>

 #include<algorithm>

 #define re register

 using namespace std;

 typedef double ld;

 typedef long long ll;

 ll sqr(ll a){return a*a;}

 #define N 1002

 struct node{ll x,y;}a[N];

 struct edge{

     int f,t; ld dis;

     edge(){}

     edge(int A,int B,ld C):

         f(A),t(B),dis(C)

     {}

     bool operator < (const edge &tmp) const{return dis<tmp.dis;}

 }b[N*N];

 int n,m,tp,fa[N],k; ld ans;

 ld dist(node A,node B){return sqrt((ld)(sqr(A.x-B.x)+sqr(A.y-B.y)));}

 int find(int x){return fa[x]==x?x:fa[x]=find(fa[x]);}

 void uni(int x,int y){

     int r1=find(x),r2=find(y);

     if(r1!=r2) fa[r2]=r1;

 }

 int main(){

     scanf("%d%d",&n,&m); int q1,q2;

     for(re int i=;i<=n;++i){

         scanf("%lld%lld",&a[i].x,&a[i].y); fa[i]=i;

         for(re int j=;j<i;++j) b[++tp]=edge(j,i,dist(a[j],a[i]));//把可能的边存起来

     }sort(b+,b+tp+);

     for(re int i=;i<=m;++i){

         scanf("%d%d",&q1,&q2);

         if(find(q1)!=find(q2)) ++k,uni(q1,q2);

     }

     for(re int i=;i<=tp&&k<n-;++i)

         if(find(b[i].f)!=find(b[i].t)){

             uni(b[i].f,b[i].t);

             ans+=b[i].dis; ++k;

         }

     printf("%.2lf",ans);

     return ;

 }