//*********************
//*???????
//*??????
//*???2013.11.1
//*********************
int main()
{
	char a[1000][101][101]={0};                                     //????????????????????????? ???????
	int n, m, number = 0;
	cin >> n;                                                       //????
	for(int i = 1; i <= n; i++)                                     //?????????
		for(int k = 1; k <= n; k++)
			cin >> a[1][i][k];
	cin >> m;                                                       //????
	for(int h = 1; h<= m; h++)
		for(int i = 1; i <= n; i++)
			for(int k = 1; k <= n; k++)
			{
				if(a[h][i][k] == '@' && a[h][i+1][k] =='.')         //??????????????????????
				{a[h+1][i+1][k] = '@';a[h+1][i][k] = '@';}
				if(a[h][i][k] == '@' && a[h][i-1][k] =='.')
				{a[h+1][i-1][k] = '@';a[h+1][i][k] = '@';}
				if(a[h][i][k] == '@' && a[h][i][k+1] =='.')
				{a[h+1][i][k+1] = '@';a[h+1][i][k] = '@';}
				if(a[h][i][k] == '@' && a[h][i][k-1] =='.')
				{a[h+1][i][k-1] = '@';a[h+1][i][k] = '@';}
				if(a[h][i][k] == '#')
					a[h+1][i][k] = '#';
				if(a[h][i][k] == '.' && a[h][i+1][k]!='@' && a[h][i-1][k]!='@' && a[h][i][k+1]!='@' && a[h][i][k-1]!='@')
					a[h+1][i][k] = '.';
			}
	for(int i = 1; i <= n; i++)
		for(int k = 1; k <= n; k++)
			{
				if(a[m][i][k] == '#'||a[m][i][k]=='.')         
					number ++;
		}
	cout <<n*n-number;                                                 //??????#?.??#????
	return 0;
}
