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<cstring>
#include<queue>
using namespace std;

int counter=2;
int Map[50][50];
int x[8] = {0,0,1,-1,1,1,-1,-1};
int y[8] = {-1,1,0,0,1,-1,1,-1};
int w,h;

void bfs(int xx,int yy){
  Map[yy][xx]=counter;
  queue<int> q;
  int pos = yy*w+xx;
  q.push(pos);
  while(!q.empty()){
    pos=q.front();
    q.pop();
    yy=pos/w;
    xx=pos%w;
    for(int k=0;k<8;k++){
      int a=xx+x[k];
      int b=yy+y[k];
      if(a < 0 || a >= w || b < 0 || b >= h) continue;
      if(Map[b][a]==1){
	Map[b][a]=counter;
	q.push(b*w+a);
      }
    }
  }
}

int main(){
  while(cin>>w>>h , w+h){
    counter=2;
    memset(Map,0,sizeof(Map));
    for(int i=0;i<h;i++){
      for(int j=0;j<w;j++){
	cin>>Map[i][j];
      }
    }

    for(int i=0;i<h;i++){
      for(int j=0;j<w;j++){
	if(Map[i][j]==1){
	  bfs(j,i);
	  counter++;
	  //     	  cout<<" i = "<<i<<" j = "<<j<<endl;
	}
      }
    }
    cout<<counter-2<<endl;
  }
  return 0;
}

C++: #include<queue>
#include<cstdio>

#define	mp	make_pair

using namespace std;

typedef	pair<int,int>	pii;

const int dx[]={1,1,0,-1,-1,-1,0,1},dy[]={0,-1,-1,-1,0,1,1,1};
int field[50][50];
bool visited[50][50];

int main(){
	for(int w,h;scanf("%d%d",&w,&h),w;){
		for(int i=0;i<h;i++)for(int j=0;j<w;j++){
			scanf("%d",field[i]+j);
			visited[i][j]=false;
		}

		int cnt=0;
		for(int i=0;i<h;i++)for(int j=0;j<w;j++){
			if(field[i][j]==1 && !visited[i][j]){
				visited[i][j]=true;
				queue<pii> qu;	qu.push(mp(i,j));
				while(!qu.empty()){
					pii a=qu.front();	qu.pop();
					for(int k=0;k<8;k++){
						int xx=a.second+dx[k],yy=a.first+dy[k];
						if(0<=xx && xx<w && 0<=yy && yy<h
						&& field[yy][xx]==1 && !visited[yy][xx]){
							qu.push(mp(yy,xx));
							visited[yy][xx]=true;
						}
					}
				}
				cnt++;
			}
		}

		printf("%d\n",cnt);
	}

	return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;

int H, W;
vector<vector<int>> field;
void dfs(int h, int w) {
    field[h][w] = 0;
    for(int dh = -1; dh <= 1; dh++) {
        for(int dw = -1; dw <= 1; dw++) {
            int nh = h + dh;
            int nw = w + dw;
            if(nh < 0 || H <= nh || nw < 0 || W <= nw) {
                continue;
            }
            if(field[nh][nw] == 0) {
                continue;
            }
            dfs(nh, nw);
        }
    }
}
int main() {
    while (cin >> W >> H) {
        if (H == 0 || W == 0) break;
        field.assign(H, vector<int>(W, 0));
        for (int h = 0; h < H; ++h) for (int w = 0; w < W; ++w) cin >> field[h][w];

        // 探索開始
        int count = 0;
        for (int h = 0; h < H; ++h) {
            for (int w = 0; w < W; ++w) {
                if (field[h][w] == 0) continue; // 残島じゃなかったらスルー
                dfs(h, w);
                ++count;
            }
        }
        cout << count << endl;
    }
}

C++: #include <bits/stdc++.h>
using namespace std;

const int dx[] = { 0, 1, 0,-1, 1, 1,-1,-1};
const int dy[] = {-1, 0, 1, 0,-1, 1, 1,-1};

int main() {
    int Map[100][100];
    while(true)
    {
        int w, h;
        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];
            }
        }

        // 左上からラスタ走査
        int res = 0;
        for(int i = 0; i < h; ++i) {
            for(int j = 0; j < w; ++j) {
                if(Map[i][j] == 1) {
                    ++res;
                    queue<pair<int,int>> que;
                    que.push(make_pair(i,j));
                    Map[i][j] = 0;
                    while(!que.empty()){
                        int x = que.front().first;
                        int y = que.front().second;
                        que.pop();
                        for(int k = 0; k < 8; ++k) {
                            int nx = x + dx[k];
                            int ny = y + dy[k];
                            if(nx < 0 || nx >= h || ny < 0 || ny >= w) continue;
                            if(Map[nx][ny] == 1) {
                                que.push(make_pair(nx, ny));
                                Map[nx][ny] = 0;
                            }
                        }
                    }
                    
                }
            }
        }
        cout << res << endl;
    }
    return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define rep(i,n) FOR(i,0,n)
#define repr(i,n) for(int i=(n)-1;0<=i;--i)
#define each(e,v) for(auto&& e:(v))
#define all(v) begin(v),end(v)
#define dump(x) cerr<<#x<<": "<<(x)<<endl
#define INF 100000000
#define IINF 9999999999999;
using vint = vector<int>;
using ll = long long;
using vll = vector<ll>;
template <class T> void chmin(T& a, const T& b) { a = min(a, b); }
template <class T> void chmax(T& a, const T& b) { a = max(a, b); }

int prime[25] = {2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97};
long long int dp[101][20] = {0};

bool earth[51][51];

void erase_island(int h, int w) {
    earth[h][w] = false;
    //cout << "# " << h << " " << w << endl;
    if(earth[h - 1][w - 1]) erase_island(h - 1, w - 1);
    if(earth[h - 1][w]) erase_island(h - 1, w);
    if(earth[h - 1][w + 1]) erase_island(h - 1, w + 1);
    if(earth[h][w + 1]) erase_island(h, w + 1);
    if(earth[h + 1][w + 1]) erase_island(h + 1, w + 1);
    if(earth[h + 1][w]) erase_island(h + 1, w);
    if(earth[h + 1][w - 1]) erase_island(h + 1, w - 1);
    if(earth[h][w - 1]) erase_island(h, w - 1);
}

int main() {
    while(true) {
        int w, h;
        cin >> w >> h;
        if(w == 0 && h == 0) break;
        rep(i, h) rep(j, w) {
                int temp;
                cin >> temp;
                if(temp == 0) earth[i][j] = false;
                else earth[i][j] = true;
            }

        int ans = 0;
        rep(i, h) rep(j, w) {
                if(earth[i][j]) erase_island(i , j), ++ans;
            }

        cout << ans << endl;
    }

    return 0;
}