import java.util.*;

public class Main {
	public static void main (String[] args) {
    	Scanner sc = new Scanner(System.in);
    	int h = sc.nextInt();
    	int w = sc.nextInt();
    	sc.nextLine();
    	boolean[][] field = new boolean[h + 2][w + 2];
    	boolean[][] used = new boolean[h + 2][w + 2];
    	for (int i = 1; i <= h; i++) {
    	    char[] arr = sc.nextLine().toCharArray();
    	    for (int j = 1; j <= w; j++) {
    	        field[i][j] = (arr[(j - 1) * 2] == '1');
    	    }
    	}
    	int count = 0;
    	for (int i = 1; i <= h; i++) {
    	    for (int j = 1; j <= w; j++) {
    	        if (field[i][j] && !used[i][j]) {
    	            count++;
    	            setUse(i, j, field, used);
    	        }
    	    }
    	}
    	System.out.println(count);
	}
	
	static void setUse(int r, int c, boolean[][] field, boolean[][] used) {
	    if (field[r][c] && !used[r][c]) {
	        used[r][c] = true;
	        if (field[r - 1][c] && !used[r - 1][c]) {
	            setUse(r - 1, c, field, used);
	        }
	        if (field[r + 1][c] && !used[r + 1][c]) {
	            setUse(r + 1, c, field, used);
	        }
	        if (field[r][c - 1] && !used[r][c - 1]) {
	            setUse(r, c - 1, field, used);
	        }
	        if (field[r][c + 1] && !used[r][c + 1]) {
	            setUse(r, c + 1, field, used);
	        }
	    }
	}
}