Go: package main

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

func getScanner(fp *os.File) *bufio.Scanner {
	scanner := bufio.NewScanner(fp)
	scanner.Split(bufio.ScanWords)
	scanner.Buffer(make([]byte, 1000005), 1000005)
	return scanner
}

func getNextString(scanner *bufio.Scanner) string {
	scanner.Scan()
	return scanner.Text()
}

func getNextInt(scanner *bufio.Scanner) int {
	i, _ := strconv.Atoi(getNextString(scanner))
	return i
}

func getNextInt64(scanner *bufio.Scanner) int64 {
	i, _ := strconv.ParseInt(getNextString(scanner), 10, 64)
	return i
}

func getNextUint64(scanner *bufio.Scanner) uint64 {
	i, _ := strconv.ParseUint(getNextString(scanner), 10, 64)
	return i
}

func getNextFloat64(scanner *bufio.Scanner) float64 {
	i, _ := strconv.ParseFloat(getNextString(scanner), 64)
	return i
}

func main() {
	fp := os.Stdin
	wfp := os.Stdout
	cnt := 0

	if os.Getenv("MASPY") == "ますピ" {
		fp, _ = os.Open(os.Getenv("BEET_THE_HARMONY_OF_PERFECT"))
		cnt = 0
	}
	if os.Getenv("MASPYPY") == "ますピッピ" {
		wfp, _ = os.Create(os.Getenv("NGTKANA_IS_GENIUS10"))
	}

	scanner := getScanner(fp)
	writer := bufio.NewWriter(wfp)
	for solve(scanner, writer) {

	}
	for i := 0; i < cnt; i++ {
		fmt.Fprintln(writer, "-----------------------------------")
		solve(scanner, writer)
	}
	writer.Flush()
}

func solve(scanner *bufio.Scanner, writer *bufio.Writer) bool {
	sol := solver{}
	sol.w = getNextInt(scanner)
	sol.h = getNextInt(scanner)
	if sol.w == 0 && sol.h == 0 {
		return false
	}
	sol.land = makeInts(sol.h, sol.w)
	for y := 0; y < sol.h; y++ {
		for x := 0; x < sol.w; x++ {
			sol.land[y][x] = getNextInt(scanner)
		}
	}
	ans := 0
	for y := 0; y < sol.h; y++ {
		for x := 0; x < sol.w; x++ {
			if sol.land[y][x] == 0 {
				continue
			}
			ans++
			sol.dfs(y, x)
		}
	}
	fmt.Fprintln(writer, ans)
	return true
}

type solver struct {
	w, h int
	land [][]int
}

func (sol *solver) dfs(y, x int) {
	if y < 0 {
		return
	}
	if y >= sol.h {
		return
	}
	if x < 0 {
		return
	}
	if x >= sol.w {
		return
	}
	if sol.land[y][x] == 0 {
		return
	}
	sol.land[y][x] = 0
	dy := [8]int{-1, -1, -1, 0, 0, 1, 1, 1}
	dx := [8]int{-1, 0, 1, -1, 1, -1, 0, 1}
	for i := 0; i < 8; i++ {
		sol.dfs(y+dy[i], x+dx[i])
	}
}
func makeInts(h, w int) [][]int {
	index := make([][]int, h, h)
	data := make([]int, h*w, h*w)
	for i := 0; i < h; i++ {
		index[i] = data[i*w : (i+1)*w]
	}
	return index
}

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;
}