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;
using ll=long long;
using vb=vector<bool>;
using vvb=vector<vb>;
using vd=vector<double>;
using vvd=vector<vd>;
using vi=vector<int>;
using vvi=vector<vi>;
using vl=vector<ll>;
using vvl=vector<vl>;
using pll=pair<ll,ll>;
using tll=tuple<ll,ll>;
using vs=vector<string>;
#define all(a) a.begin(),a.end()
#define rall(a) a.rbegin(),a.rend()
#define rep(i,n) range(i,0,n)
#define rrep(i,n) for(int i=(n)-1;i>=0;i--)
#define range(i,a,n) for(int i=(a);i<(n);i++)

#define LINF    	((ll)1ll<<60)
#define INF     	((int)1<<30)
#define EPS     	(1e-9)
#define MOD     	(1000000007ll)
#define fcout(a)	cout<<setprecision(a)<<fixed
#define fs 			first
#define sc			second
#define PI			3.1415926535897932384

int dx[]={1,0,-1,0,1,-1,-1,1},dy[]={0,1,0,-1,1,1,-1,-1};
template<class S,class T>ostream&operator<<(ostream&os,pair<S,T>p){os<<"["<<p.first<<", "<<p.second<<"]";return os;};
template<class S>auto&operator<<(ostream&os,vector<S>t){bool a=1; for(auto s:t){os<<(a?"":" ")<<s; a=0;} return os;}
void OUT(bool b){cout<<(b?"YES":"NO")<<endl;}
void Out(bool b){cout<<(b?"Yes":"No")<<endl;}
void out(bool b){cout<<(b?"yes":"no")<<endl;}
int popcnt(int x) { return __builtin_popcount(x); }
int popcnt(ll x) { return __builtin_popcountll(x); }
int clz(int x) { return 31 - __builtin_clz(x); }
int clz(ll x) { return 63 - __builtin_clzll(x); }
int ctz(int x) { return __builtin_ctz(x); }
int ctz(ll x) { return __builtin_ctzll(x); }

class compare {
public:
	bool operator()(tuple<ll, ll> a, tuple<ll, ll> b) {
		return (get<1>(a) > get<1>(b));
	}
};

void solve(int h,int w){
	int in;
	int ans=0;
	vvb vv(h+2,(vb(w+2,false)));
	rep(i,h){
		rep(j,w){
			cin>>in;
			vv[i+1][j+1]=(in==1);
		}
	}
	rep(i,h){
		rep(j,w){
			if(vv[i+1][j+1]){
				stack<pll> stk;
				stk.push(pll(i+1,j+1));
				while(!stk.empty()){
					int x,y;
					tie(x,y)=stk.top();stk.pop();
					vv[x][y]=false;
					rep(k,8){
						if(vv[x+dx[k]][y+dy[k]])stk.push(pll(x+dx[k],y+dy[k]));
					}
				}
				ans++;
			}
		}
	}
	cout<<ans<<endl;
}
int main(){
	cin.tie(0);
	ios::sync_with_stdio(false);
	int w,h;
	while(cin>>h>>w,h){
		solve(w,h);
	}
}

C++: #include <cstdio>
#include <cstring>
using namespace std;

int w, h;
int map[100][100];
int island_number[100][100];

int angle[][2] = {
	{-1, 0}, {-1, -1}, {0, -1}, {1, -1},
	{1, 0}, {1, 1}, {0, 1}, {-1, 1}
};

void dfs(int y, int x)
{
	for (int i = 0; i < 8; i++){
		if (
		y + angle[i][0] >= 0 &&
		y + angle[i][0] < h &&
		x + angle[i][1] >= 0 &&
		x + angle[i][1] < w &&
		island_number[y + angle[i][0]][x + angle[i][1]] == (y + angle[i][0]) * h + x + angle[i][1]
		){
			island_number[y + angle[i][0]][x + angle[i][1]] = island_number[y][x];
			dfs(y + angle[i][0], x + angle[i][1]);
		}
	}
}

int main()
{
	
	while (scanf("%d %d", &w, &h), w + h){
		memset(island_number, 0, sizeof(island_number));
		
		for (int i = 0; i < h; i++){
			for (int j = 0; j < w; j++){
				scanf("%d", &map[i][j]);
				if (map[i][j] == 1){
					island_number[i][j] = i * h + j;
				}
				else {
					island_number[i][j] = -1;
				}
			}
		}
		
		for (int i = 0; i < h; i++){
			for (int j = 0; j < w; j++){
				if (island_number[i][j] == i * h + j && island_number[i][j] >= 0){
					dfs(i, j);
				}
			}
		}
		
		bool ex[100 * 100] = {false};
		for (int i = 0; i < h; i++){
			for (int j = 0; j < w; j++){
				if (island_number[i][j] >= 0){
					ex[island_number[i][j]] = true;
				}
//				printf("%d ", island_number[i][j]);
			}
//			puts("");
		}
		
		int cnt = 0;
		for (int i = 0; i < w * h; i++){
			cnt += ex[i];
		}
		
		printf("%d\n", cnt);
	}
	
	return 0;
}

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

int H, W;
vector<vector<int> > field;

void dfs(int y, int x) {
	field[y][x] = 0;

	for (int dy = -1; dy <= 1; dy++) {
		for (int dx = -1; dx <= 1; dx++) {
			int ny = y + dy;
			int nx = x + dx;

			if (ny < 0 || H <= ny) continue;
			if (nx < 0 || W <= nx) continue;
			if (field[ny][nx] == 0) continue;

			dfs(ny, nx);
		}
	}
}

int main(void) {

	while (cin >> W >> H) {
		if (H == 0 || W == 0) break;

		// フィールド入力
		field.assign(H, vector<int>(W, 0));
		for (int y = 0; y < H; y++) for (int x = 0; x < W; x++) cin >> field[y][x];

		// 探索
		int count = 0;
		for (int y = 0; y < H; y++) {
			for (int x = 0; x < W; x++) {
				if (field[y][x] == 0) continue;
				dfs(y, x);
				count++;
			}
		}
		cout << count << endl;
	}

	return 0;
}