#include <iostream>

 #include<cstdio>

 #include<cstring>

 #include<algorithm>

 #include<stdlib.h>

 using namespace std;

 #define N 100010

 #define M 1000010

 #define LL long long

 LL dp[M<<],p[N];

 struct node

 {

     int u,v,next;

 }ed[M<<];

 int head[N],t,n,m;

 void init()

 {

     t = ;

     memset(head,-,sizeof(head));

 }

 void add(int u,int v)

 {

     ed[t].u = u;

     ed[t].v = v;

     ed[t].next = head[u];

     head[u] = t++;

 }

 LL dfs(int pre,int u,int e)

 {

     int i;

     LL sum=p[u];

     for(i = head[u] ; i != - ; i = ed[i].next)

     {

         int v = ed[i].v;

         if(v==pre)

         continue;

         sum+=dfs(u,v,i);

     }

     dp[e] = sum;

     return dp[e];

 }

 int main()

 {

     int i,kk=;

     while(scanf("%d%d",&n,&m)!=EOF)

     {

         if(n==&&m==)

         break;

         init();kk++;

         memset(dp,,sizeof(dp));

         LL s=;

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

         {

             scanf("%lld",&p[i]);

             s+=p[i];

         }

         for(i = ; i <= m ;i++)

         {

             int u,v;

             scanf("%d%d",&u,&v);

             add(u,v);

             add(v,u);

         }

         dfs(-,i,);

         LL ans = s,o;

         for(i =  ; i < t ; i++)

         {

             if(s-dp[i]>dp[i])

             o = s-dp[i]-dp[i];

             else

             o = dp[i]-(s-dp[i]);

             if(o<ans)

             ans = o;

         }

         printf("Case %d: ",kk);

         printf("%lld\n",ans);

     }

     return ;

 }