#include <stdio.h>#include <cstring>using namespace std;struct node{ int u; int next;};__int64 min(__int64 a , __int64 b ){ return a>b?b:a;}node edge[100005*10];int n,m;__int64 stu[100005];__int64 all=0;__int64 dp[100005];__int64 ans;int head[100005];int visited[100005];int count;void addEdge(int c , int d){ edge[count].u=d; edge[count].next=head[c]; head[c]=count++; edge[count].u=c; edge[count].next=head[d]; head[d]=count++;}__int64 abs(__int64 a){ return a>0?a:-a;}void init(){ memset(dp,0,sizeof(dp)); memset(visited,0,sizeof(visited)); all=0; count=0; memset(head,-1,sizeof(head)); memset(edge,0,sizeof(edge));}void dfs(int u){ visited[u]=1; dp[u]=stu[u]; for(int i=head[u];i!=-1;i=edge[i].next)//其中i指的是边，v是边指向的点 { int v=edge[i].u; if(visited[v]==0) { dfs(v); dp[u]=dp[u]+dp[v]; } }}int k=1;int main(){ while(1) { scanf("%d%d",&n,&m); if(n+m==0) { break; } init(); for(int i=1;i<=n;i++) { scanf("%I64d",&stu[i]); all+=stu[i]; } for(int i=0;i<m;i++) { int a,b; scanf("%d%d",&a,&b); addEdge(a,b); } dfs(1); ans=abs(all-2*dp[1]); for(int i=2;i<=n;i++) { ans=min(ans,abs(all-2*dp[i])); } printf("Case %d: %I64dn",k++,ans); } return 0;}
