#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
const int MAXN = 1010;
int disx[2] = {0,-1};
int disy[2] = {-1,0};
struct Node{
    int x, y, v;
    friend bool operator < (Node a, Node b){
        return a.v < b.v;
    }
};
Node dt[MAXN * MAXN * 2];
int mp[MAXN][MAXN];
int hsh[MAXN][MAXN];
class Map{
    private:
        int N, M;
    public:
        Map(){
            N = 0;
            M = 0;
        }
        Map(int N, int M){
            this->N = N;
            this->M = M;
            int tp = 0;
            for(int i = 1; i <= N; i++){
                for(int j = 1; j <= M; j++){
                    scanf("%d",&mp[i][j]);
                    hsh[i][j] = ++tp;
                }
            }
        }
        void getdt(int &tp){
        //    cout << N << " " << M << endl;
            for(int i = 1; i <= N; i++){
                for(int j = 1; j <= M; j++){
                    for(int k = 0; k < 2; k++){
                        int nx, ny;
                        nx = i + disx[k];
                        ny = j + disy[k];
                        if(nx <= 0 || ny <= 0 || nx > N || ny > M)
                            continue;
                        dt[tp].x = hsh[nx][ny];
                        dt[tp].y = hsh[i][j];
                        dt[tp].v = abs(mp[nx][ny] - mp[i][j]);
                        tp++;
                    }
                }
            }
        }
};
int pre[MAXN * MAXN];
class Kruth{
    private:
        
    public:
        Kruth(){
            for(int i = 1; i <= MAXN * MAXN; i++){
                pre[i] = i;
            }
        }
        int find(int r){
            int x = r;
            while(r != pre[r]){
                r = pre[r];
            }
            int i = x, j;
            while(i != r){
                j = pre[i];
                pre[i] = r;
                i = j;
            }
            return r;
        }
        void merge(int x, int y, int v, int &ans){
            int f1 = find(x), f2 = find(y);
            if(f1 != f2){
                pre[f1] = f2;
                ans += v;
            }
        }
};
int main(){
    int T;
    int kase = 0;
    cin >> T;
    while(T--){
        int N, M;
        cin >> N >> M;
        Map a(N,M);
        int tp = 0;
        int ans = 0;
        a.getdt(tp);
        sort(dt, dt + tp);
        Kruth kru;
        for(int i = 0; i < tp; i++){
            kru.merge(dt[i].x, dt[i].y, dt[i].v, ans);
        }
        printf("Case #%d:\n%d\n",++kase,ans);
    }
    return 0;
}