1 #include<cstdio>
 2 #include<queue>
 3 #include<algorithm>
 4 #include<cstring>
 5 #include<cmath>
 6 using namespace std;
 7 
 8 int G[1005][1005];
 9 int vis[1005][1005];
10 int d[4][2]={1,0,0,1,-1,0,0,-1};
11 int m,n;
12 const int inf=0x3f3f3f3f;
13 
14 int cal(int x1,int y1,int x2,int y2)
15 {
16     return abs(G[x1][y1]-G[x2][y2]);
17 };
18 
19 struct lowercost
20 {
21     int x,y;
22     int cost;
23     bool operator < (const lowercost &temp)const
24     {
25         return cost>temp.cost;
26     }
27 };
28 
29 void init()
30 {
31     memset(vis,0,sizeof(vis));
32 }
33 
34 int prim()
35 {
36     priority_queue<lowercost>q;
37     lowercost t1,t2;
38     int sum=0,i,cnt;
39     t1.x=t1.y=t1.cost=0;
40     q.push(t1);
41     cnt=0;
42     while(!q.empty())
43     {
44         t1=q.top();
45         q.pop();
46         if(vis[t1.x][t1.y])
47         continue;
48         vis[t1.x][t1.y]=1;
49         sum+=t1.cost;
50         for(i=0;i<4;i++)
51         {
52             t2.x=t1.x+d[i][0];
53             t2.y=t1.y+d[i][1];
54             t2.cost=cal(t1.x,t1.y,t2.x,t2.y);
55             if(t2.x>=0&&t2.x<m&&t2.y>=0&&t2.y<n&&!vis[t2.x][t2.y])
56             q.push(t2);
57         }
58     }
59     return sum;
60 }
61 
62 int main()
63 {
64     int t,i;
65     scanf("%d",&t);
66     for(i=1;i<=t;i++)
67     {
68         init();
69         scanf("%d%d",&m,&n);
70         for(int i=0;i<m;i++)
71         for(int j=0;j<n;j++)
72         scanf("%d",&G[i][j]);
73         int ans=prim();
74         printf("Case #%d:\n",i);
75         printf("%d\n",ans);
76     }
77     return 0;
78 }