/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{	public static int[] dr = {1,1,0,-1,-1,-1,0,1};
	public static int[] dc = {0,1,1,1,0,-1,-1,-1};
	public static int floodFill(int row, int column, int one, int zero, int size, int[][] grid) {
		if (row < 0 || row>= size || column < 0 || column >= size ) {
			return 0;
		}
		if(grid[row][column] != one) {
			return 0;
		}
		int answer = 1;
		grid[row][column] = zero;
		for (int d = 0; d < 8; d++) {
		answer += floodFill(row + dr[d], column + dc[d], 1, 0, size, grid);
		}
		return answer;
	}
	public static void main (String[] args) throws java.lang.Exception
	{
		Scanner kb = new Scanner(System.in);
		while (kb.hasNextInt()) {
			int size = kb.nextInt();
			int[][] graph = new int[size][size];
			for (int i = 0; i < size; i++) {
				String temp = kb.next();
				for (int j = 0; j < size; j++) {
					graph[i][j] = Character.getNumericValue(temp.charAt(j));
				}
			}
			System.out.println(floodFill(0,3,1,0,size,graph));
		}
	}
}

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001010 
000000
110000
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010100
8
01100101
01000001 
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10000001
01100000