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 <cstdio>

using namespace std;

int w, h;
int field[50][51];

void dfs(int x, int y)
{
	field[x][y] = 0;
	
	for(int dx = -1; dx <= 1; dx++){
		for(int dy = -1; dy <= 1; dy++){
			int nx = x + dx;
			int ny = y + dy;
			
			if(0 <= nx && nx < w && 0 <= ny && ny < h && field[nx][ny] == 1) dfs(nx, ny);
		}
	}
	return ;
}

void solve(){
	int res = 0;
	for(int i = 0; i < w; i++){
		for(int j = 0; j < h; j++){
			if(field[i][j] == 1){
				dfs(i, j);
				res++;
			}
		}
	}
	printf("%d\n", res);
}

int main()
{
	while(scanf("%d %d", &w, &h) != EOF){
		if(w == 0 && h == 0){ break; }
		for(int i = 0; i < h; i++){
			for(int j = 0; j < w; j++){
				scanf("%d", &field[i][j]);
			}
		}
		solve();
	}
	
	return 0;
}

C++: 
using namespace std;

static const int N = 52;

void dfs(int map[][N], int pi, int pj){
	const int di[] = {-1,0,1,1,1,0,-1,-1};
	const int dj[] = {1,1,1,0,-1,-1,-1,0};

	if( map[pi][pj] == 0 ){
		return ;
	}

	map[pi][pj] = 0;

	for(int i = 0; i < sizeof(di)/sizeof(di[0]); i++){
		dfs(map, pi + di[i], pj + dj[i] );
	}
}

int main(void){
	ws(cin);
	while( 1 ){
		int count = 0;
		int n, m;
		int map[N][N] = {{0,},};

		cin >> n >> m;
		if( n == 0 && m == 0 ){
			break;
		}

		for(int i = 0; i < m; i++ ){
			for(int j = 0; j < n; j++){
				cin >> map[j + 1][i + 1];
			}
		}

		for(int i = 0; i < m; i++ ){
			for(int j = 0; j < n; j++){
				if(map[j + 1][i + 1]){
					dfs(map, j + 1, i + 1);
					count++;
				}
			}
		}

		cout << count << "\n";
	}
	return 0;
}

C++: #include<iostream>
using namespace std;
const int MAXW = 51;
const int MAXH = 51;
int map[MAXW][MAXH];
int w,h;
int dx[] = {-1,0,1,-1,1,-1,0,1};
int dy[] = {1,1,1,0,0,-1,-1,-1};
int dfs(int x,int y){
  if(map[x][y] == 0)return 0;
  map[x][y] = 0;
  for(int i = 0;i < 9;i++){
    int nx = x+dx[i];
    int ny = y+dy[i];
    if(nx >= 0 && nx < w & ny >= 0 && ny < h)
      dfs(nx,ny);
  }
  return 1;
}

int main(){
  while(true){
    cin >> w >> h;
    if(w == 0 && h == 0)break;
    for(int i = 0;i < h;i++){
      for(int j = 0;j < w;j++){
        cin >> map[i][j];
      }
    }
    int count = 0;
    for(int i = 0;i < h;i++){
      for(int j = 0;j < w;j++){
        count += dfs(j,i);
      }
    }
    cout << count << endl;
  }
}

C++: #include <iostream>
#include <vector>
#include <algorithm>

typedef long long ll;
using namespace std;

int H, W;
vector<vector<int>> C;
vector<vector<int>> visited;
int ans = 0;





void dfs(int &i, int &j){
    visited[i][j] = 1;
    for(int y=-1; y<=1; y++){
        for(int x=-1; x<=1; x++){
            int ny = i+y;
            int nx = j+x;
            
            if(ny>=0 && ny<H && nx>=0 && nx<W && C[ny][nx] && !visited[ny][nx]) dfs(ny, nx);
        }
    }
    return;
}




int main() {
    while(1){
        ans = 0;
        visited.clear();
        
        cin >> W >> H; if((W&H)==0) break;
        C.resize(H);
        for(vector<int> &v:C) v.resize(W);
        for(vector<int> &row:C)
            for(int &c:row) cin >> c;

        visited.resize(H);
        for(vector<int> &v:visited) v.resize(W);

        for(int i=0; i<H; i++){
            for(int j=0; j<W; j++){
                if(C[i][j] && !visited[i][j]){
                    dfs(i,j);
                    ans ++;
                }
            }
        }
        
        
        cout << ans << endl;
    }
    return 0;
}

C++: #include<bits/stdc++.h>
#define rep(i,n) for(int i = 0; i < n; ++i)
#define rrep(i,n) for(int i = 1; i <= n; ++i)
using namespace std;
//using ll=long long;
const int MX = 2200000;
//const ll LINF = 1000000000000000000ll;
//const long long MOD = 1000000007;
//long long INF = 90000000001000;
int w,h;
bool seen[50][50];
int c[50][50];
int d[2]={1,-1};
void dfs(int i,int j){
    seen[i][j]=true;
    for (int k = 0; k < 2; ++k)
    {
       if (!seen[i+d[k]][j]&&i+d[k]<h&&i+d[k]>=0&&c[i+d[k]][j])dfs(i+d[k],j);
       if (!seen[i][j+d[k]]&&j+d[k]<w&&j+d[k]>=0&&c[i][j+d[k]])dfs(i,j+d[k]);
       if (!seen[i+d[k]][j-d[k]]&&i+d[k]<h&&i+d[k]>=0&&j-d[k]>=0&&j-d[k]<w&&c[i+d[k]][j-d[k]])dfs(i+d[k],j-d[k]);
       if (!seen[i+d[k]][j+d[k]]&&i+d[k]<h&&i+d[k]>=0&&j+d[k]<w&&j+d[k]>=0&&c[i+d[k]][j+d[k]])dfs(i+d[k],j+d[k]); 
    }

}


int main(){


while(1){
cin >> w >> h;
if(w==0&&h==0) break;
for (int i = 0; i < h; ++i)
{
   for (int j = 0; j < w; ++j)
   {
       cin >> c[i][j];
       seen[i][j]=false;
   }
}
int cnt=0;
for (int i = 0; i < h; ++i)
{
  for (int j = 0; j < w; ++j)
  {
    if(c[i][j]==1&&!seen[i][j]){cnt++;dfs(i,j);}
  }
}
cout << cnt << endl;
}

return 0;

}