Go: package main

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

const (
	initialBufSize = 100000
	maxBufSize     = 1000000
)

var sc *bufio.Scanner

func initScanner(r io.Reader) *bufio.Scanner {
	buf := make([]byte, initialBufSize)

	sc := bufio.NewScanner(r)
	sc.Buffer(buf, maxBufSize)
	sc.Split(bufio.ScanWords) // bufio.ScanLines
	return sc
}

func main() {
	sc = initScanner(os.Stdin)
	resolve()
}

func resolve() {
	results := []int{}
	for true {
		w, h := scanInt(sc), scanInt(sc)
		if w == 0 && h == 0 {
			break
		}
		grid := make([][]int, h)
		for i := 0; i < h; i++ {
			grid[i] = make([]int, w)
			for j := 0; j < w; j++ {
				grid[i][j] = scanInt(sc)
			}
		}
		num := 0
		for i := range loop0(h) {
			for j := range loop0(w) {
				start := pos{y: i, x: j}
				if grid[start.y][start.x] == 0 {
					continue
				}
				num++
				_dfs(grid, w, h, start)
			}
		}
		results = append(results, num)
	}
	for _, v := range results {
		fmt.Println(v)
	}
	return
}

func _dfs(grid [][]int, w, h int, start pos) {
	grid[start.y][start.x] = 0
	for _, df := range []pos{
		pos{1, 0}, pos{-1, 0},
		pos{0, -1}, pos{0, 1},
		pos{1, 1}, pos{-1, -1},
		pos{-1, 1}, pos{1, -1},
	} {
		np := addPos(start, df)
		if np.y < 0 || h <= np.y || np.x < 0 || w <= np.x {
			continue
		}
		if grid[np.y][np.x] == 0 {
			continue
		}
		_dfs(grid, w, h, np)
	}
}

type pos struct{ x, y int }

func addPos(p, d pos) pos {
	return pos{
		x: p.x + d.x,
		y: p.y + d.y,
	}
}

func loop0(n int) chan int {
	return loop(0, n-1, 1)
}

func loop1(n int) chan int {
	return loop(1, n, 1)
}

func loop(s, e, d int) chan int {
	ch := make(chan int)
	go func() {
		for i := s; i <= e; i += d {
			ch <- i
		}
		close(ch)
	}()
	return ch
}

// snip-scan-funcs
func scanInt(sc *bufio.Scanner) int {
	sc.Scan()
	i, _ := strconv.Atoi(sc.Text())
	return int(i)
}
func scanString(sc *bufio.Scanner) string {
	sc.Scan()
	return sc.Text()
}

C++: #include <iostream>
#include <string>
#include <algorithm>
#include <functional>
#include <vector>
#include <utility>
#include <cstring>
#include <iomanip>
#include <numeric>
#include <limits>
#include <cmath>
#include <cassert>
#include <queue>

using namespace std;
using ll = long long;

const int INF = 1<<30;
const int MOD = (int)1e9 + 7;
const int MAX_N = (int)1e5 + 5;
const int dy[] = {1, 0, -1, 0, 1, 1, -1, -1};
const int dx[] = {0, 1, 0, -1, 1, -1, 1, -1};
#define debug(x) cout << #x << ": " << x << endl

int W, H;

void bfs(int y, int x, const vector<vector<int>> &table, vector<vector<int>> &flag)
{
    using P = pair<int, int>;
    queue<P> que;
    que.push(P(y, x));
    flag[y][x] = 0;
    while(que.size())
    {
        P p = que.front(); que.pop();
        for(int i = 0; i < 8; i++)
        {
            int ny = p.first + dy[i];
            int nx = p.second + dx[i];
            if(ny < 0 or nx < 0 or ny >= H or nx >= W) continue;
            if(table[ny][nx] == 0 or not flag[ny][nx]) continue;
            flag[ny][nx] = 0;
            que.push(P(ny, nx));
        }
    }
}

signed main(void)
{
    cin.tie(0);
    ios::sync_with_stdio(false);
    while(cin >> W >> H, W or H)
    {
        vector<vector<int>> table(H, vector<int>(W));
        for(int i = 0; i < H; i++)
        {
            for(int j = 0; j < W; j++) cin >> table[i][j];
        }
        vector<vector<int>> flag = table;
        int ans = 0;
        for(int i = 0; i < H; i++)
        {
            for(int j = 0; j < W; j++)
            {
                if(not flag[i][j]) continue;
                ans++;
                bfs(i, j, table, flag);
            }
        }
        cout << ans << endl;
    }
    return 0;
}

C++: #include <iostream>
#include <cstdio>
using namespace std;
char field[51][51];
int W, H;

void dfs(int x, int y) {
  //cout << "field[x][y] = " << field[x][y] << endl;
  field[x][y] = '0';
  
  for(int dx = -1 ; dx <= 1 ; dx++) {
    for(int dy = -1 ; dy <= 1 ; dy++) {
      int nx = x + dx, ny = y + dy;
      if(0 <= nx && nx < H && 0 <= ny && ny < W && field[nx][ny] == '1') dfs(nx, ny);
    }
  }
}

int main(void) {
  while(cin >> W >> H, W != 0 && H != 0) {
    int res = 0;
    for(int i = 0 ; i < H ; i++)
      for(int j = 0 ; j < W ; j++) cin >> field[i][j];
    
    for(int i = 0 ; i < W ; i++) {
      for(int j = 0 ; j < H ; j++) {
	if(field[i][j] == '1') {
	  dfs(i, j);
	  res++;
	  /*cout << endl;
	  for(int b = 0 ; b < H ; b++) {
	    for(int a = 0 ; a < W ; a++) {
	      cout << field[b][a] << ' ';
	    }
	    cout << endl;
	  }
	  cout << endl;*/
	}
      }
    }
    cout << res << endl;
  }
  return 0;
}

C++: #include "bits/stdc++.h"

using namespace std;

typedef pair<int, int> P;

int main() {
	cin.tie(0);
	ios::sync_with_stdio(false);

    int w,h;
    int dx[8]={1,1,1,0,-1,-1,-1,0},dy[8]={-1,0,1,1,1,0,-1,-1};
    while(cin>>w>>h,w||h){
        vector< vector<int> > field(h,vector<int>(w));
        for(int i=0;i<h;i++){
            for(int j=0;j<w;j++){
                cin>>field[i][j];
            }
        }
        int res=0;
        for(int i=0;i<h;i++){
            for(int j=0;j<w;j++){
                if(field[i][j]){
                    //cout<<i<<" "<<j<<endl;
                    queue<P> q;
                    field[i][j]=0;
                    q.push(P(i,j));
                    while(!q.empty()){
                        P p=q.front();q.pop();
                        for(int k=0;k<8;k++){
                            int nx=p.first+dx[k],ny=p.second+dy[k];
                            if(nx<0||h<=nx||ny<0||w<=ny) continue;
                            if(field[nx][ny]==0) continue;
                            field[nx][ny]=0;
                            q.push(P(nx,ny));
                        }
                    }
                    res++;
                }
            }
        }
        cout<<res<<endl;
    }
}

C++: #include<iostream>
#include<vector>
#include<string>
using namespace std;

vector<vector<int>>tisei;
int tate, yoko;
void shima(int a, int b) {
	tisei[a][b] = 0;
	for (int c = a-1; c < a+2; c++) {
		for (int d = b - 1; d < b + 2; d++) {
			if (c > -1 && d > -1 && c< tate&d < yoko&&tisei[c][d])shima(c, d);
		}
	}
}
int main() {
	int a, b;
	while (cin >> a >> b, a | b) {
		tate = b;
		yoko = a;
		tisei.clear();
		for (int c = 0; c < b; c++) {
			vector<int>o(a);
			for (int e = 0; e < a; e++) {
				cin >> o[e];
			}
			tisei.push_back(o);
		}
		int s = 0;
		for (int g = 0; g < b; g++) {
			for (int h = 0; h < a; h++) {
				if (tisei[g][h]) { s++;  shima(g, h); }
			}
		}
		cout << s << endl;
	}
}