import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;


public class Main  {

	public static int rows;
	public static int cols;
	public static ArrayList<String>grid;
	public static boolean [][]visited;
	public static int cnt;

	public static boolean isValid(int r,int c)
	{
		if((r>=0 && r<rows) && (c>=0 && c<cols))
			return true;
		else
			return false;
	}

	public static void floodFill(int r,int c)
	{
		if(!isValid(r,c) || grid.get(r).charAt(c)=='0' || visited[r][c])
			return;

		visited[r][c]=true;
		cnt++;

		floodFill(r+1, c); // Down
		floodFill(r-1, c); // UP
		floodFill(r, c-1); // Left
		floodFill(r, c+1); // Right
		floodFill(r-1, c-1); // UP-Left
		floodFill(r+1, c-1); // Down -Left
		floodFill(r-1, c+1); // UP - Right
		floodFill(r+1, c+1); // Down - Right

	}

	public static void main(String[] args) throws NumberFormatException, IOException {
		BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
		StringBuilder ans = new StringBuilder();
		int t = Integer.parseInt(in.readLine());
		in.readLine();
		for(int i=0;i<t;i++)
		{
			cnt =0;
			grid = new ArrayList<String>();
			String temp;
			while((temp = in.readLine())!=null && temp.length()!=0 )
				grid.add(temp);

			rows = grid.size();
			cols = grid.get(0).length();
			visited = new boolean [rows][cols];
			for(int j=0;j<rows;j++)
			{
				for(int k=0;k<cols;k++)
				{
					int tm = cnt;
					cnt=0;
					if(!visited[j][k] && grid.get(j).charAt(k)!='0')
						floodFill(j, k);
					cnt = Math.max(cnt, tm);
				}
			}
			ans.append(cnt).append("\n");
			if(i!=t-1)
				ans.append("\n");
		}
		System.out.print(ans.toString());
	}
}