using System;
using System.Collections.Generic;
using System.Linq;

class Program
{
    static void Main(string[] args)
    {
        var tokens = Console.ReadLine().Split().Select(int.Parse).ToList();
        var h = tokens[0];
        var w = tokens[1];

        var field = new List<List<int>>();
        for (int i = 0; i < h; i++)
        {
            var row = Console.ReadLine().Split().Select(int.Parse).ToList();
            field.Add(row);
        }

        int counter = 0;
        for (int x = 0; x < h; x++)
        {
            for (int y = 0; y < w; y++)
            {
                if (field[x][y] == 0)
                {
                    continue;
                }

                counter++;

                var queue = new Queue<Tuple<int, int>>();
                queue.Enqueue(Tuple.Create(x, y));
                while (queue.Any())
                {
                    var coordinate = queue.Dequeue();
                    var x1 = coordinate.Item1;
                    var y1 = coordinate.Item2;
                    for (int dx = -1; dx <= 1; dx++)
                    {
                        for (int dy = -1; dy <= 1; dy++)
                        {
                            if (Math.Abs(dx + dy) != 1)
                            {
                                continue;
                            }

                            var x2 = x1 + dx;
                            var y2 = y1 + dy;
                            if (0 <= x2 && x2 < h && 0 <= y2 && y2 < w && field[x2][y2] == 1) {
                                field[x2][y2] = 0;
                                queue.Enqueue(Tuple.Create(x2, y2));
                            }
                        }
                    }

                }
            }
        }

        Console.WriteLine(counter);
    }
}