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;

int w,h;
int field[51][51];

// 現在地(x,y)
void dfs(int x, int y){
    // 今いるところを-1に置き換える
    field[y][x] = -1;

    // 移動する8方向をループ
    for(int dx = -1 ; dx <= 1 ; dx++ ){
        for(int dy = -1 ; dy <= 1 ; dy++ ){
            // x方向にdx, y方向にdy, 移動した場所を(mx,my)とする
            int mx = x + dx;
            int my = y + dy;
            // 範囲外に出たときは次の処理へ
            if( mx < 0 || my < 0 || mx >= w || my >= h ) continue;
            // 陸地だったら再帰呼び出し
            if( field[my][mx] == 1 ){
                dfs( mx , my );
            }
        }
    }
}

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

        int ans = 0;
        for(int y=0 ; y < h ; y++ ){
            for(int x=0 ; x < w ; x++ ){
                if( field[y][x] == 1 ){ // 陸地があったら再帰関数を呼び出す
                    dfs( x , y );
                    ans++;
                }
            }
        }
        cout << ans << endl;
    }
}

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

#define __sel(_1, _2, x, ...) x

#define repn(i, n) for (ll i = 0; i < (n); i++)
#define repr(i, a, b) for (ll i = (a); i < (b); i++)
#define rep(i, ...) __sel(__VA_ARGS__, repr, repn)(i, __VA_ARGS__)

#define rrepn(i, n) for (ll i = (n - 1); i >= 0; i--)
#define rrepr(i, a, b) for (ll i = (b - 1); i >= (a); i--)
#define rrep(i, ...) __sel(__VA_ARGS__, rrepr, rrepn)(i, __VA_ARGS__)

#define umax(m, x) (m = max(m, x))
#define umin(m, x) (m = min(m, x))
#define rng(v) v.begin(), v.end()
#define rrng(v) v.rbegin(), v.rend()
#define bit(x, n) ((x) >> (n) & 1)

#define pb push_back
#define mp make_pair
#define mt make_tuple
#define fi first
#define se second

#define pt(x) cout << (x) << endl;
#define shv(v) for (auto __t1 : v) cerr << __t1 << " "; cerr << endl;
#define db(x) cerr << #x << ": " << (x) << endl;
#define dbv(v) cerr << #v << ": "; shv(v);
#define dbm(m) cerr << #m << ":" << endl; for (auto __t2 : m) { shv(__t2); }

using namespace std;

using ll = long long int;
using ld = long double;
using pii = pair<int, int>;
using pll = pair<ll, ll>;

using vi = vector<int>;
using vl = vector<ll>;
using vd = vector<double>;
using vld = vector<ld>;
using vb = vector<bool>;
using vc = vector<char>;
using vs = vector<string>;
using vpii = vector<pii>;
using vpll = vector<pll>;

using vvi = vector<vector<int>>;
using vvl = vector<vector<ll>>;
using vvd = vector<vector<double>>;
using vvld = vector<vector<ld>>;
using vvb = vector<vector<bool>>;
using vvc = vector<vector<char>>;
using vvs = vector<vector<string>>;

const int INF = 1e9;
const ll LINF = 1e18;
const ll MOD = 1e9 + 7;

inline int gi() { int x; cin >> x; return x; }
inline ll gl() { int x; cin >> x; return x; }
inline char gc() { char x; cin >> x; return x; }
inline string gs() { string x; cin >> x; return x; }

inline vi gvi(int n) { vi v(n); rep(i, n) cin >> v[i]; return v; }
inline vl gvl(int n) { vl v(n); rep(i, n) cin >> v[i]; return v; }
inline vc gvc(int n) { vc v(n); rep(i, n) cin >> v[i]; return v; }
inline vs gvs(int n) { vs v(n); rep(i, n) cin >> v[i]; return v; }

inline vvi gvvi(int h, int w) { vvi m(h, vi(w)); rep(i, h) rep(j, w) cin >> m[i][j]; return m; }
inline vvl gvvl(int h, int w) { vvl m(h, vl(w)); rep(i, h) rep(j, w) cin >> m[i][j]; return m; }
inline vvc gvvc(int h, int w) { vvc m(h, vc(w)); rep(i, h) rep(j, w) cin >> m[i][j]; return m; }
inline vvs gvvs(int h, int w) { vvs m(h, vs(w)); rep(i, h) rep(j, w) cin >> m[i][j]; return m; }

inline void yn(bool f) { cout << (f ? "Yes" : "No") << endl; }


int w, h;

void dfs(vvi& m, vvb& e, int x, int y) {
    if (e[y][x]) return;
    e[y][x] = true;
    rep(i, max(0, y - 1), min(h, y + 2)) {
        rep(j, max(0, x - 1), min(w, x + 2)) {
            if (j == x && i == y) continue;
            if (m[i][j])
                dfs(m, e, j, i);
        }
    }
}

int main() {
    while (true) {
        w = gi();
        h = gi();
        if (w == 0 && h == 0) break;

        vvi m = gvvi(h, w);
        vvb e(h, vb(w, false));
        int cnt = 0;
        rep(i, h) rep(j, w) {
            if (m[i][j] && !e[i][j]) {
                cnt++;
                dfs(m, e, j, i);
            }
        }
        pt(cnt);    
    }

    return 0;
}