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

#define SZ(a) (int)a.size()
#define ALL(a) a.begin(), a.end()
#define FOR(i, a, b) for (int i = (a); i<(b); ++i)
#define RFOR(i, b, a) for (int i = (b)-1; i>=(a); --i)
#define MP make_pair
#define PB push_back
#define F first
#define S second
#define FILL(a, b) memset(a, b, sizeof(a))

typedef long long LL;
typedef pair<int, int> PII;
typedef vector<int> VI;
typedef double db;


const int N = 1 << 20;
string s[N];
string t[N];

int n, m;
void resize(){
	VI d2(n);
	int dL = 0, dR = 0, mx = 0;
	for(int i=0,l=-1,r=-1;i<n;i++)
    {
        if(i<=r)
            d2[i] = min(r-i+1,d2[l+(r-i)+1]);
        while(i+d2[i]<n && i-(d2[i]+1)>=0 && s[i+d2[i]] == s[i-(d2[i]+1)]) ++d2[i]; 
        if(i + d2[i] > r)
        {
            r = i + d2[i] - 1;
            l = i - d2[i];
        }
        if(i - d2[i] == 0 && dL < d2[i]){
			dL = d2[i];
			mx = max(mx, i);
		}
		if(i + d2[i] == n && dR < d2[i])
			dR = d2[i];
		
    }
    if(dL == 0 && dR == 0)
		return;
	if(dL < dR){
		reverse(s, s + n);
		resize();
		return;
	}
		
	FOR(i, 0, n){
		if(mx + i >= n){
			n = i;
			break;
		}
		s[i] = s[mx + i];
	}
//	cout << n << " " << m << endl;
    
    //delete rows;
	
}
void transpose(){
	FOR(j, 0, m){
		t[j] = "";
		FOR(i, 0, n)
			t[j] += s[i][j];
	}
	FOR(i, 0, m)
		s[i] = t[i];
	swap(n, m);
}

bool ok(int i, int j){
	return 0 <= i && i < n && 0 <= j && j < m;
}
int id(int i, int j){
	return i * m + j;
}
int dx[4] = {0, 0, -1, 1};
int dy[4] = {-1, 1, 0, 0};

bool used[N];
void dfs(int i, int j){
	used[id(i, j)] = 1;
	
	FOR(it, 0, 4){
		int ni = i + dx[it];
		int nj = j + dy[it];
		
		if(!ok(ni, nj) || used[id(ni, nj)] || s[ni][nj] == '1')
			continue;
		dfs(ni, nj);
	}
}

void solve(){
	cin >> n >> m;
	FOR(i, 0, n)
		cin >> s[i];
	
	FOR(it0, 0, 2){
		FOR(it1, 0, 2){
			resize();
			
			reverse(s, s + n);
		}
		transpose();
	}
	
	int ans = 0;
	FOR(i, 0, n)
		FOR(j, 0, m)
			if(s[i][j] == '0' && !used[id(i, j)]){
				dfs(i, j);
				ans++;
			}
	cout << ans << "\n";
	FOR(i, 0, n * m)
		used[i] = 0;
}

int main()
{
	ios::sync_with_stdio(false);
	cin.tie(0);


	int te;
	cin >> te;
	
	while(te--)
		solve();
		
	//cerr << 1.0 * clock() / CLOCKS_PER_SEC << endl;
	
	
	return 0;
}