#include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;
const int maxn = 55;
int N,m;
char G[maxn][maxn];
 bool check(char a, char b)
 {
       if(a == b || a == ‘G‘)
              return true;
        else
             return false;
}
int solve() {
    int ret = 0;

    for (int i = 0; i < N; i++) {

        for (int j = 0; j < m; j++) {
            if (check(G[i][j], ‘R‘) && !check(G[i-1][j-1], ‘R‘))
               ret++;
            if (check(G[i][j], ‘B‘) && !check(G[i-1][j+1], ‘B‘))
               ret++;
        }
    }
    return ret;
}

     int main () {
   int cas;
    scanf("%d", &cas);
   while(cas--) {
        scanf("%d", &N);
        memset(G, 0, sizeof(G));
       for (int i = 0; i < N; i++)
            scanf("%s", G[i]);
              m = strlen(G[0]) ;
          printf("%d\n", solve());
 }
    return 0;
}