ps_em

using namespace std;
ll n,m;
ll hit[105][105];
ll wat[105][105];
bool vis1[105][105];
bool vis2[105][105];
vector<ll>vokhit;
ll cka,cpa;
void dfs(int r,int c)
{
    if(r>n || r<1 || c<1 || c>m)
    {
        wat[cka][cpa]=0;

        return;

    }
    if(vis1[r][c])
        return;


    if(r==1 || r==n || c==1 || c==m)
    {
        wat[cka][cpa]=0;
        return;
    }

    vis1[r][c]=1;
    ll loki = hit[r][c+1];
    ll poki = hit[r][c];
    if(loki<=poki)
    {
        dfs(r,c+1);
    }
    if(hit[r+1][c]<=hit[r][c])
    {
        dfs(r+1,c);
    }
    if(hit[r-1][c]<=hit[r][c])
    {
        dfs(r-1,c);
    }

    if(hit[r][c-1]<=hit[r][c])
    {
        dfs(r,c-1);
    }

}
int pok(int r,int c)
{
    if(r==1 || r==n || c==1 || c==m)
        return 1;
    return 0;
}
ll dfs2(int r,int c)
{

    if(vis2[r][c])
        return INF;


    if(r==1 || r==n || c==1 || c==m)
    {
        return hit[r][c];
    }


    if(wat[r][c])
    {
        vokhit.pb(hit[r][c]);

    }
    else
    {
        return hit[r][c];
    }

    vis2[r][c]=1;
    ll mni = INF;


    mni = min(mni,dfs2(r+1,c));

    mni = min(mni,dfs2(r-1,c));

    mni = min(mni,dfs2(r,c+1));

    mni = min(mni,dfs2(r,c-1));

    return mni;


}
int main()
{
    //freopen("out.txt","w",stdout);
    int tc;
    sfi(tc);
    while(tc--)
    {

        scanf("%lld %lld",&n,&m);
        loop(i,1,n)
        {
            loop(j,1,m)
            {
                wat[i][j]=1;
            }
        }



        loop(r,1,n)
        {
            loop(c,1,m)
            {
                cin>>(hit[r][c]);
            }
        }


        ms(vis1,false);
        loop(r,1,n)
        {
            loop(c,1,m)
            {
                ms(vis1,false);
                cka = r,cpa =c;
                dfs(r,c);
            }
        }
        ll ans = 0;
        ms(vis2,false);

        loop(r,1,n)
        {
            loop(c,1,m)
            {

                if(wat[r][c] && !vis2[r][c])
                {
                    cka = r,cpa =c;
                    ll wall =  dfs2(r,c);
                    for(int ix=0; ix<SZ(vokhit); ix++)
                    {
                        if(vokhit[ix]<wall)
                            ans+=(wall-vokhit[ix]);
                    }
                    vokhit.clear();


                }

            }
        }

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


    }



    return 0;
}