Go: package main

import (
	"bufio"
	"fmt"
	"io"
	"math"
	"os"
	"strconv"
)

var (
	readString func() string
	readBytes  func() []byte
	stdout     *bufio.Writer
)

func init() {
	readString, readBytes = newReadString(os.Stdin)
	stdout = bufio.NewWriter(os.Stdout)
}

func newReadString(ior io.Reader) (func() string, func() []byte) {
	r := bufio.NewScanner(ior)
	r.Buffer(make([]byte, 1024), math.MaxInt32)
	r.Split(bufio.ScanWords)

	f1 := func() string {
		if !r.Scan() {
			panic("Scan failed")
		}
		return r.Text()
	}
	f2 := func() []byte {
		return []byte(f1())
	}
	return f1, f2
}

func readInt() int {
	return int(readInt64())
}

func readInt64() int64 {
	i, err := strconv.ParseInt(readString(), 10, 64)
	if err != nil {
		panic(err.Error())
	}
	return i
}

func readFloat64() float64 {
	f, err := strconv.ParseFloat(readString(), 64)
	if err != nil {
		panic(err.Error())
	}
	return f
}

func printf(f string, args ...interface{}) (int, error) {
	return fmt.Fprintf(stdout, f, args...)
}

func println(args ...interface{}) (int, error) {
	return fmt.Fprintln(stdout, args...)
}

func eprintln(args ...interface{}) (int, error) {
	return fmt.Fprintln(os.Stderr, args...)
}

func eprintf(f string, args ...interface{}) (int, error) {
	return fmt.Fprintf(os.Stderr, f, args...)
}

func min(a, b int) int {
	if a < b {
		return a
	}
	return b
}

func min64(a, b int64) int64 {
	if a < b {
		return a
	}
	return b
}

func max(a, b int) int {
	if a < b {
		return b
	}
	return a
}

func max64(a, b int64) int64 {
	if a < b {
		return b
	}
	return a
}

func abs(a int) int {
	if a < 0 {
		return -a
	}
	return a
}

func abs64(a int64) int64 {
	if a < 0 {
		return -a
	}
	return a
}

func gcd(a, b int) int {
	if b == 0 {
		return a
	}
	return gcd(b, a%b)
}

func gcd64(a, b int64) int64 {
	if b == 0 {
		return a
	}
	return gcd64(b, a%b)
}

// readString() string
// readInt() int
// readInt64() int64
// readFloat64() float64

// -----------------------------------------------------------------------------

func main() {
	defer stdout.Flush()

	for {
		ans, ok := solve()
		if !ok {
			break
		}
		println(ans)
	}

}

func solve() (int, bool) {
	w := readInt()
	h := readInt()
	if w == 0 && h == 0 {
		return 0, false
	}

	c := make([][]int, h+2)
	c[0] = make([]int, w+2)
	c[h+1] = make([]int, w+2)
	for i := 1; i-1 < h; i++ {
		c[i] = make([]int, w+2)
		for j := 1; j-1 < w; j++ {
			c[i][j] = readInt()
		}
	}

	var ans int
	for i := 1; i-1 < h; i++ {
		for j := 1; j-1 < w; j++ {
			if 0 < c[i][j] {
				ans++
				dfs(c, i, j)
			}
		}
	}
	return ans, true
}

func dfs(c [][]int, y, x int) {
	c[y][x] = 0
	dx := []int{-1, 0, 1, -1, 1, -1, 0, 1}
	dy := []int{-1, -1, -1, 0, 0, 1, 1, 1}
	for i := range dx {
		nx := x + dx[i]
		ny := y + dy[i]
		if 0 < c[ny][nx] {
			dfs(c, ny, nx)
		}
	}
}

// -----------------------------------------------------------------------------

C++: #include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
using namespace std;
using ll = long long;
using P = pair<int, int>;
const int INF = 1001001001;
const int MOD = 1000000007;

template <typename T>
void print(const T &v);

vector<vector<int>> grid(55, vector<int>(55, -1));
vector<vector<bool>> seen(55, vector<bool>(55, false));

void dps(int x, int y)
{
    int xs[8] = {1, -1, 0, 0, -1, -1, 1, 1};
    int ys[8] = {0, 0, 1, -1, -1, 1, -1, 1};
    for (int i = 0; i < 8; i++)
    {
        int nx = x + xs[i];
        int ny = y + ys[i];
        if (nx < 0 || ny < 0)
        {
            continue;
        }
        if (seen[nx][ny] || grid[nx][ny] != 1)
        {
            continue;
        }
        seen[nx][ny] = true;
        dps(nx, ny);
    }
}

void init()
{
    for (int i = 0; i < 55; i++)
    {
        for (int j = 0; j < 55; j++)
        {
            grid[i][j] = -1;
            seen[i][j] = false;
        }
    }
}
int main()
{
    while (1)
    {
        int w, h;
        cin >> w >> h;
        if (w == 0 || h == 0)
        {
            return 0;
        }
        init();
        for (int i = 0; i < h; i++)
        {
            for (int j = 0; j < w; j++)
            {
                cin >> grid[i][j];
            }
        }
        int cnt = 0;
        for (int i = 0; i < h; i++)
        {
            for (int j = 0; j < w; j++)
            {
                if (seen[i][j] || grid[i][j] != 1)
                {
                    continue;
                }
                ++cnt;
                dps(i, j);
            }
        }
        cout << cnt << endl;
    }
}

// Use For Debug
template <typename T>
void print(T const &v)
{
    for (int i = 0; i < v.size(); i++)
    {
        if (i)
            cout << ' ';
        cout << v[i];
    }
    cout << endl;
}

C++: #include <cstdio>

using namespace std;

char mp[60][60] = {0};
int dx[9] = {0, 0, 1, -1, 1, -1, 1, -1};
int dy[9] = {1, -1, 0, 0, 1, -1,-1,  1};

void def(int y, int x){
	mp[y][x] = 0;
	for (int i = 0; i < 8; i++){
		int ty = y + dy[i];
		int tx = x + dx[i];
		if (mp[ty][tx] == '1') def(ty, tx);
	}
}

int main()
{
	int w, h;
	int pi, pj;
	int cnt;
	while (scanf("%d %d", &w, &h), !(w == 0 && h == 0)){
		cnt = 0;
		
		for (int i = 0; i < h; i++){
			for (int j = 0; j < w; j++){
				scanf("%s", &mp[i][j]);
			}
		}
		
		for (int i = 0; i < h; i++){
			for (int j = 0; j < w; j++){
				if (mp[i][j] == '1'){
					def(i, j);
					cnt++;
				}
			}
		}
		
		printf("%d\n", cnt);
	}
}