using System;
using System.Linq;
using System.Collections.Generic;
using Debug = System.Diagnostics.Trace;
using SB = System.Text.StringBuilder;
using Number = System.Int64;
namespace Program
{
    public class Solver
    {
        public void Solve()
        {
            for (; ; )
            {
                var w = ri;
                var h = ri;
                if (w + h == 0) return;
                var s = Enumerate(h, x => Enumerate(w, y => ri));
                var id = Enumerate(h, x => new int[w]);
                for (int i = 0; i < h; i++)
                    for (int j = 0; j < w; j++)
                        id[i][j] = -1;
                for (int i = 0; i < h; i++)
                    for (int j = 0; j < w; j++)
                    {
                        if (s[i][j] == 0) continue;
                        if (id[i][j] != -1) continue;
                        var q = new Queue<int>();
                        q.Enqueue(i * w + j);
                        id[i][j] = i * w + j;
                        while (q.Any())
                        {
                            var p = q.Dequeue();
                            var px = p / w;
                            var py = p % w;
                            //Debug.WriteLine($"{px} {py}");
                            for (int dx = -1; dx <= 1; dx++)
                                for (int dy = -1; dy <= 1; dy++)
                                {
                                    var nx = px + dx;
                                    var ny = py + dy;
                                    if (nx < 0 || nx >= h || ny < 0 || ny >= w) continue;
                                    if (s[nx][ny] == 0) continue;
                                    if (id[nx][ny] == -1)
                                    {
                                        id[nx][ny] = i * w + j;
                                        q.Enqueue(nx * w + ny);
                                    }
                                }
                        }
                    }
                Console.WriteLine(id.SelectMany(x => x).Distinct().Count(x => x != -1));
            }
        }
        const long INF = 1L << 60;
        //int[] dx = { -1, 0, 1, 0 };
        //int[] dy = { 0, 1, 0, -1 };
        //*
        int ri { get { return sc.Integer(); } }
        long rl { get { return sc.Long(); } }
        double rd { get { return sc.Double(); } }
        string rs { get { return sc.Scan(); } }
        //*/

        public IO.StreamScanner sc = new IO.StreamScanner(Console.OpenStandardInput());
        static T[] Enumerate<T>(int n, Func<int, T> f) { var a = new T[n]; for (int i = 0; i < n; ++i) a[i] = f(i); return a; }
        static public void Swap<T>(ref T a, ref T b) { var tmp = a; a = b; b = tmp; }
    }
}

#region main
static class Ex
{
    static public string AsString(this IEnumerable<char> ie) { return new string(ie.ToArray()); }
    static public string AsJoinedString<T>(this IEnumerable<T> ie, string st = " ")
    {
        return string.Join(st, ie.Select(x => x.ToString()).ToArray());
        //return string.Join(st, ie);
    }
    static public void Main()
    {
        Console.SetOut(new System.IO.StreamWriter(Console.OpenStandardOutput()) { AutoFlush = false });
        var solver = new Program.Solver();
        solver.Solve();
        Console.Out.Flush();
    }
}
#endregion
#region Ex
namespace Program.IO
{
    using System.IO;
    using System.Text;
    using System.Globalization;
    public class Printer: StreamWriter
    {
        public override IFormatProvider FormatProvider { get { return CultureInfo.InvariantCulture; } }
        public Printer(Stream stream) : base(stream, new UTF8Encoding(false, true)) { }
    }
    public class StreamScanner
    {
        public StreamScanner(Stream stream) { str = stream; }
        public readonly Stream str;
        private readonly byte[] buf = new byte[1024];
        private int len, ptr;
        public bool isEof = false;
        public bool IsEndOfStream { get { return isEof; } }
        private byte read()
        {
            if (isEof) return 0;
            if (ptr >= len) { ptr = 0; if ((len = str.Read(buf, 0, 1024)) <= 0) { isEof = true; return 0; } }
            return buf[ptr++];
        }
        public char Char() { byte b = 0; do b = read(); while ((b < 33 || 126 < b) && !isEof); return (char)b; }

        public string Scan()
        {
            var sb = new StringBuilder();
            for (var b = Char(); b >= 33 && b <= 126; b = (char)read())
                sb.Append(b);
            return sb.ToString();
        }
        public string ScanLine()
        {
            var sb = new StringBuilder();
            for (var b = Char(); b != '\n' && b != 0; b = (char)read())
                if (b != '\r') sb.Append(b);
            return sb.ToString();
        }
        public long Long() { return isEof ? long.MinValue : long.Parse(Scan()); }
        public int Integer() { return isEof ? int.MinValue : int.Parse(Scan()); }
        public double Double() { return isEof ? double.NaN : double.Parse(Scan(), CultureInfo.InvariantCulture); }
    }
}
#endregion


Measured memory_bytes: 11236