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 <iostream>
#include <cstdio>
#include <stack>
#include <utility>
using namespace std;
#define rep(i,n) for(int i=0;i<(n);i++)
#define FST first
#define SEC second

typedef pair <int,int> pxy;

int dfs(int map[][50],int w,int h){
  int dd[10]={0, 1, 1, 1, 0, -1, -1, -1, 0, 1};
  stack <pxy> s;
  int num=0;
  rep(y,h){
    rep(x,w){
      if(map[x][y]==1){
	s.push(pxy(x,y));
	while(!s.empty()){
	  int cx=s.top().FST,cy=s.top().SEC;
	  s.pop();
	  map[cx][cy]=0;
	  rep(r,8){
	    int nx=cx+dd[r],ny=cy+dd[r+2];
	    if(nx<0||w<=nx||ny<0||h<=ny||map[nx][ny]==0) continue;
	    s.push(pxy(nx,ny));
	  }
	}
	num++;
      }
    }
  }
  return num;
}

int main() {
  for(;;){
    int w,h,x,y;
    scanf("%d %d",&w,&h);
    int map[50][50];
    if(w==0&&h==0) break;
    rep(i,h){
      rep(j,w){
	cin >> map[j][i];
      }
    }
    cout << dfs(map,w,h) << endl;
  } 
}

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

int main() {
    int n, m;
    int dx[] = {1, 0, -1, 0, 1, 1, -1, -1};
    int dy[] = {0, 1, 0, -1, 1, -1, 1, -1};
    while (cin >> m >> n, n || m) {
        vector<vector<int>> v(n, vector<int>(m));
        for (auto& i : v) for (auto& j : i) cin >> j;

        int count = 0;
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < m; j++) {
                if (v[i][j] == 0) continue;
                count++;
                queue<pair<int,int>> que;
                que.push(make_pair(i, j));

                while (que.size()) {
                    auto p = que.front();
                    que.pop();
                    int x = p.first;
                    int y = p.second;

                    if (v[x][y] == 0) continue;

                    v[x][y] = 0;

                    for (int k = 0; k < 8; k++) {
                        int nx = x + dx[k];
                        int ny = y + dy[k];

                        if (0 <= nx && nx < n && 0 <= ny && ny < m && v[nx][ny] == 1) {
                            que.push(make_pair(nx, ny));
                        }
                    }
                }
            }
        }

        cout << count << endl;
    }

    return 0;
}

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;
}