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>
using namespace std;

void exploreIsland( bool c[50][50], int h, int w, int y, int x )
{
    c[y][x] = 0;

    if( y - 1 >= 0 && c[y-1][x] == 1 )
        exploreIsland( c, h, w, y - 1, x ); 
    if( x - 1 >= 0 && y - 1 >= 0 && c[y-1][x-1] == 1 )
        exploreIsland( c, h, w, y - 1, x - 1 ); 
    if( x + 1 < w && y - 1 >= 0 && c[y-1][x+1] == 1 )
        exploreIsland( c, h, w, y - 1, x + 1 );
    if( x - 1 >= 0 && c[y][x-1] == 1 )
        exploreIsland( c, h, w, y, x - 1 ); 
    if( x + 1 < w && c[y][x+1] == 1 )
        exploreIsland( c, h, w, y, x + 1 );
    if( y + 1 < h && c[y+1][x] == 1 )
        exploreIsland( c, h, w, y + 1, x ); 
    if( x - 1 >= 0 && y + 1 < h && c[y+1][x-1] == 1 )
        exploreIsland( c, h, w, y + 1, x - 1 ); 
    if( x + 1 < w && y + 1 < h && c[y+1][x+1] == 1 )
        exploreIsland( c, h, w, y + 1, x + 1 ); 
}

int main()
{
    int h, w;
    bool c[50][50];

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

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

int w, h;
int field[60][60];

void dfs(int x, int y) {
  field[y][x] = 0;
  for(int i = -1; i <= 1; i++) {
    for(int j = -1; j <= 1; j++) {
      int tx = x+j, ty = y+i;
      if(0 <= tx && tx < w && 0 <= ty && ty < h && field[ty][tx] == 1) dfs(tx, ty);
    }
  }
}

int main() {
  while(cin >> w >> h, w+h) {
    for(int i = 0; i < h; i++) {
      for(int j = 0; j < w; j++) {
	cin >>field[i][j];
      }
    }

    int ans = 0;
    for(int i = 0; i < h; i++) {
      for(int j = 0; j < w; j++) {
	if(field[i][j]) {
	  ans++;
	  dfs(j, i);
	}
      }
    }
    cout << ans << endl;
  }
}

C++: #include<iostream>
#include<cmath>
#include<algorithm>
#include<string>
#include<vector>
#include<stack>
#include<queue>
#include<set>
#include<map>
#include<iomanip>
#include<bitset>
using namespace std;
typedef long long ll;
typedef pair<ll,ll> P;
typedef pair<ll,P> P1;
typedef pair<P,P> P2;
#define pu push
#define pb push_back
#define mp make_pair
#define eps 1e-7
#define INF 1000000000
#define fi first
#define sc second
#define rep(i,x) for(ll i=0;i<x;i++)
#define repn(i,x) for(ll i=1;i<=x;i++)
#define SORT(x) sort(x.begin(),x.end())
#define ERASE(x) x.erase(unique(x.begin(),x.end()),x.end())
#define POSL(x,v) (lower_bound(x.begin(),x.end(),v)-x.begin())
#define POSU(x,v) (upper_bound(x.begin(),x.end(),v)-x.begin())

const int MAX = 510000;
const int MOD = 1000000007;

// 四方向への移動ベクトル
const int dx[8] = {1, 0, -1, 0, 1, 1, -1, -1};
const int dy[8] = {0, 1, 0, -1, 1, -1, 1, -1};

// 入力
int H, W;
vector<vector<ll> > field;

// 探索
bool seen[51][51]; // seen[h][w] := マス (h, w) が検知済みかどうか
void dfs(int h, int w) {
    seen[h][w] = true;

    // 四方向を探索
    for (int dir = 0; dir < 8; ++dir) {
        int nh = h + dx[dir];
        int nw = w + dy[dir];

        // 場外アウトしたり、移動先が壁の場合はスルー
        if (nh < 0 || nh >= H || nw < 0 || nw >= W) continue;
        if (field[nh][nw] == 0) continue;

        // 移動先が探索済みの場合
        if (seen[nh][nw]) continue;

        // 再帰的に探索
        dfs(nh, nw);
    }
}

int main(){
  vector<ll> ans;
  while(1){
    cin >> W >> H;
    if(H == 0 and W == 0) break;
    field.clear();
    field.resize(H); rep(j,H) field[j].resize(W);
    rep(i,H) rep(j,W) cin >> field[i][j];

    rep(i,51) rep(j,51) seen[i][j] = false;
    ll tmp = 0;
    rep(i,H){
      rep(j,W){
        if(field[i][j] == 1 and seen[i][j] == false){
          dfs(i,j);
          tmp++;
        }
      }
    }
    ans.pb(tmp);
  }
  rep(i,ans.size()) cout << ans[i] << endl;
}

C++: //41
#include<iostream>

using namespace std;

int w,h;
bool imap[50][50];

void ff(int y,int x){
  imap[y][x]=false;
  for(int i=-1;i<=1;i++){
    for(int j=-1;j<=1;j++){
      int ny=y+i,nx=x+j;
      if(0<=ny&&ny<h&&0<=nx&&nx<w&&imap[ny][nx]){
	ff(ny,nx);
      }
    }
  }
}

int main(){
  for(;cin>>w>>h,w|h;){
    fill_n(&imap[0][0],50*50,false);
    for(int y=0;y<h;y++){
      for(int x=0;x<w;x++){
	cin>>imap[y][x];
      }
    }
    int ans=0;
    for(int y=0;y<h;y++){
      for(int x=0;x<w;x++){
	if(imap[y][x]){
	  ans++;
	  ff(y,x);
	}
      }
    }
    cout<<ans<<endl;
  }
  return 0;
}