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 <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < n; i++)

vector<int> dx = {1, 1, 1, -1, -1, -1, 0, 0}, dy = {1, -1, 0, 1, -1, 0, 1, -1};
int w, h;
vector<vector<bool>> field;

void dfs(int x, int y)
{
  field.at(y).at(x) = false;
  rep(direction, 8)
  {
    int nx = x + dx.at(direction), ny = y + dy.at(direction);
    if (0 <= nx && nx < w && 0 <= ny && ny < h && field.at(ny).at(nx))
    {
      dfs(nx, ny);
    }
  }
}

int main()
{
  while (1)
  {
    cin >> w >> h;
    if (!w && !h)
    {
      break;
    }
    field.resize(h, vector<bool>(w));
    field.assign(h, vector<bool>(w, false));
    rep(y, h)
    {
      rep(x, w)
      {
        int c;
        cin >> c;
        if (c)
        {
          field.at(y).at(x) = true;
        }
      }
    }
    int ans = 0;
    rep(y, h)
    {
      rep(x, w)
      {
        if (field.at(y).at(x))
        {
          dfs(x, y);
          ans++;
        }
      }
    }
    cout << ans << endl;
  }
}

C++: #include <bits/stdc++.h>

using namespace std;

// Repetitions
#define FOR(i,a,n) for(ll i = ((ll) a); i < ((ll) n); ++i)
#define FORR(i, s, g) for(ll i = ((ll)s - 1); i >= ((ll) g); --i)
#define REP(i, n) FOR(i, 0, n)
#define REPR(i, n) FORR(i, n, 0)

// Container Utils
#define ALL(v) (v).begin(), (v).end()
#define RALL(v) (v).rbegin(), (v).rend()
#define SORTALL(v) sort(ALL(v))
#define SZ(a) int((a).size())
#define CLR(a) memset((a), 0 ,sizeof(a))
#define EACH(i,c) for(typeof((c).begin()) i=(c).begin(); i!=(c).end(); ++i)
#define EXIST(s,e) ((s).find(e)!=(s).end())

// For Debug
#define DMP(x)  cerr << #x << " = " << (x) << endl
#define DBG(x) cerr << #x << " = " << (x) << " (L" << __LINE__ << ")" << " " << __FILE__ << endl

// Aliases
#define PB push_back
#define MP make_pair
typedef long long ll;
typedef string str;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<long long> vll;
typedef vector<string> vs;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<pii> vpii;
typedef vector<pll> vpll;

// I/O Asynchronizing
struct aaa{
    aaa(){
        cin.tie(0); ios::sync_with_stdio(0); cout<<fixed<<setprecision(20);
    };
}aaaaaaa;

#define MAX_H 50
#define MAX_W 50

int h, w;
bool is_land[MAX_H][MAX_W] = { false };

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

inline bool is_in_range(const int y, const int x) {
    return 0 <= y && y < h && 0 <= x && x < w;
}

void dfs(const int y, const int x) {
    is_land[y][x] = false;
    REP(i, 8) {
        int nx = x + dx[i], ny = y + dy[i];
        if(is_in_range(ny, nx) && is_land[ny][nx]) dfs(ny, nx);
    }
}

int main() {
    while(true) {
        cin >> w >> h;
        if(w == 0 && h == 0) break;
        REP(j, h) {
            REP(i, w) {
                int c;
                cin >> c;
                is_land[j][i] = (c == 1);
            }
        }
        int ans = 0;
        REP(j, h) {
            REP(i, w) {
                if(is_land[j][i]) {
                    dfs(j, i);
                    ans++;
                }
            }
        }
        cout << ans << endl;
    }

    return 0;
}