#include <bits/stdc++.h>
using namespace std;

// #pragma comment(linker, "/STACK:1073741824")



#define mem(x, n) memset(x, n, sizeof(x))
#define ll long long 
#define pll pair<long long, long long>
#define vll vector<ll>
#define vpll vector<pair<int, int>>
#define forn(i, n) for (int i = 0; i < int(n); ++i)
#define all(x) (x).begin(), (x).end()
#define pb push_back
#define ff first
#define ss second
#define YES cout << "YES\n"
#define NO cout << "NO\n"
#define nl "\n"


int n,m;   
vector<string>v;
int vis[3010][3010] ;
map<int,set<pll>>map_of_colors_pos;
map<int,int>map_of_colors ;
int clr  ;

bool is_val ( int i, int j) {
    if( i < 0 or i >= n or j < 0 or j >= m )
        return 0;
    return 1;
}

void dfs( int i , int j ) {
    if( !is_val(i,j) ) return ;
    if( v[i][j] == 'B' ) return;
    if( vis[i][j] == 1 ) return ; 
    if( v[i][j] == '.' ) {
        map_of_colors_pos[clr].insert({i,j});
        return;
    }
    

    vis[i][j] = 1;
    map_of_colors[clr]++;

    dfs(i+1,j) ;
    dfs(i-1,j) ;
    dfs(i,j+1) ;
    dfs(i,j-1) ;  


}


void solve() { 
    
    cin>>n>>m;
    ll ans = 0  ; 
    v.clear();
    map_of_colors_pos.clear();
    map_of_colors.clear();

    for( int i =0 ;i<n;i++ ) {
        string s;  cin>>s;
        v.pb(s);
    }
   
    for( int i = 0; i<n;i++  ) {
        for( int j =0;j<m;j++ ) {
            vis[i][j] = -1 ;
        }
    }

    clr = 0 ;

    for( int i = 0; i<n;i++  ) {
        for( int j = 0;j<m;j++ ) {
            if( v[i][j] == 'W' and vis[i][j] == -1 ) {
                clr ++ ;
                dfs(i,j) ;
            }
        }
    }
    
    // cout << clr << nl;

    map<pll,ll>mmm;

    for( auto it : map_of_colors_pos ) {
        if( it.ss.size() == 1 ) {
            auto x = *it.ss.begin() ; 
            // cout << x.ff << " " << x.ss << nl; 
            mmm[x] += map_of_colors[it.ff] ;
        }
    }

    for( auto it : mmm ) {
        ans =  max ( ans , it.ss  );
    }

    cout << ans << nl; 

}
 
static void run_with_stack_size(void (*func)(void), size_t stsize) {
    char *stack, *send;
    stack = (char *)malloc(stsize);
    send = stack + stsize - 16;
    send = (char *)((uintptr_t)send / 16 * 16);
    asm volatile(
        "mov %%esp, (%0)\n"
        "mov %0, %%esp\n"
        :
        : "r"(send));
    func();
    asm volatile("mov (%0), %%esp\n" : : "r"(send));
    free(stack);

}

int main() {
    
    
    

    ios::sync_with_stdio(0);
    cin.tie(0);

     

#ifndef ONLINE_JUDGE
     freopen("inputa.txt" , "r" , stdin);
     freopen("output2.txt", "w", stdout);
#endif

    int t = 1;
    cin >> t;
    

// Case #1: YES
    for( int i=1;i<=t;i++ )  {

        cout << "Case #" << i << ":" ; 
 run_with_stack_size( solve , 1024 * 1024 * 1024);
       
    } 


    
    
   
}

#include<bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
using namespace std;

#ifndef ONLINE_JUDGE
#include "../debug.cpp"
#else
#define debug(...)
#define debugArr(...)
#endif

void pre_pro(){
}
void dxt(){
}

static void run_with_stack_size(void (*func)(void), size_t stsize) {
    char *stack, *send;
    stack = (char *)malloc(stsize);
    send = stack + stsize - 16;
    send = (char *)((uintptr_t)send / 16 * 16);
    asm volatile(
        "mov %%rsp, (%0)\n"
        "mov %0, %%rsp\n"
        :
        : "r"(send));
    func();
    asm volatile("mov (%0), %%rsp\n" : : "r"(send));
    free(stack);
}
signed main(){
    ios_base::sync_with_stdio(false); cin.tie(NULL);
    pre_pro();
    int T = 1;
    // cin >> T;
    for (int i = 1; i <= T; i++) {
        run_with_stack_size(dxt, 1024 * 1024 * 1024);
    }
    return 0;
}

/var/folders/jn/k5x6mwn10bv_m2w6w2y4_qbr0000gn/T//ccM0dJDF.s:483:6: error: unknown token in expression
        mov %rsp, (x1)
            ^
/var/folders/jn/k5x6mwn10bv_m2w6w2y4_qbr0000gn/T//ccM0dJDF.s:483:6: error: invalid operand
        mov %rsp, (x1)
            ^
/var/folders/jn/k5x6mwn10bv_m2w6w2y4_qbr0000gn/T//ccM0dJDF.s:484:9: error: unknown token in expression
mov x1, %rsp
        ^
/var/folders/jn/k5x6mwn10bv_m2w6w2y4_qbr0000gn/T//ccM0dJDF.s:484:9: error: invalid operand
mov x1, %rsp
        ^
/var/folders/jn/k5x6mwn10bv_m2w6w2y4_qbr0000gn/T//ccM0dJDF.s:488:12: error: unknown token in expression
        mov (x1), %rsp
                  ^
/var/folders/jn/k5x6mwn10bv_m2w6w2y4_qbr0000gn/T//ccM0dJDF.s:488:12: error: invalid operand
        mov (x1), %rsp
                  ^
[Finished in 842ms with exit code 1]