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#include
   
    #include
    
     #include
     
      using namespace std;int ans1 = 0;int ans2 = 0;int b[1005][1005] = {    0 };char a[1005][1005];int c[1005];int flag = 0;void dfs(int x, int y,int k){   	if (a[x][y] != '#'||b[x][y]==1)		return;	if (a[x][y] == '#' && a[x + 1][y] == '#' && a[x - 1][y] == '#' && a[x][y + 1] == '#' && a[x][y - 1] == '#')	{   		c[k] = 1;	}		flag = 1;		b[x][y] = 1;		dfs(x + 1, y,k);		dfs(x - 1, y,k);		dfs(x, y - 1,k);		dfs(x, y + 1,k);}int main(int argc, char const* argv[]){   	int n;	cin >> n;	int cnt = 0;	for (int i = 0; i <= n; i++)		for (int j = 0; j <= n; j++)		{   			a[i][j] = '#';		}	for (int i = 1; i <= n; i++)		for (int j = 1; j <= n; j++)		{   			cin >> a[i][j];		}	for (int i = 1; i <= n; i++)		for (int j = 1; j <= n; j++)		{   			flag = 0;			dfs(i, j,ans1);			if (flag == 1)			{   				ans1++;			}		}	for (int i = 0; i < ans1; i++)	{   		if (c[i] == 1)			ans2++;	}	cout << ans1 - ans2 << endl;	/*for (int i = 1; i <= n; i++)	{		for (int j = 1; j <= n; j++)		{			cout << a[i][j];		}		cout << endl;	}*/	return 0;}