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)
		}
	}
}

// -----------------------------------------------------------------------------

Python: import sys

sys.setrecursionlimit(10**5)

def solve():
    while 1:
        w, h = map(int, sys.stdin.readline().split())

        if w == h == 0:
            return

        room = [[int(j) for j in sys.stdin.readline().split()] for i in range(h)]

        cnt = 0

        for i in range(h):
            for j in range(w):
                if room[i][j]:
                    cnt += 1
                    dfs(w, h, room, i, j)

        print(cnt)

def dfs(w, h, room, i, j):
    if i < 0 or i >= h or j < 0 or j >= w or (not room[i][j]):
        return

    room[i][j] = 0

    dfs(w, h, room, i + 1, j)
    dfs(w, h, room, i - 1, j)
    dfs(w, h, room, i, j + 1)
    dfs(w, h, room, i, j - 1)
    dfs(w, h, room, i + 1, j + 1)
    dfs(w, h, room, i + 1, j - 1)
    dfs(w, h, room, i - 1, j + 1)
    dfs(w, h, room, i - 1, j - 1)

if __name__ == '__main__':
    solve()

C++: #include <bits/stdc++.h>
using namespace std;
int ans = 1e9;
int H,W;
int mp[50][50];
int nx,ny;
void func(int y,int x){
	//cout << y << ' ' <<x<<endl;
	if(mp[y][x] == 1){
		mp[y][x] = 2;
		func(y,x);
	}
	if(mp[y+1][x] == 1){
		mp[y+1][x] = 2;
		func(y+1,x);
	}
	if(mp[y][x+1] == 1){
		mp[y][x+1] = 2;
		func(y,x+1);
	}
	if(mp[y+1][x+1] == 1){
		mp[y+1][x+1] = 2;
		func(y+1,x+1);
	}
	if(mp[y-1][x] == 1){
		mp[y-1][x] = 2;
		func(y-1,x);
	}
	if(mp[y][x-1] == 1){
		mp[y][x-1] = 2;
		func(y,x-1);
	}
	if(mp[y-1][x-1] == 1){
		mp[y-1][x-1] = 2;
		func(y-1,x-1);
	}
	if(mp[y+1][x-1] == 1){
		mp[y+1][x-1] = 2;
		func(y+1,x-1);
	}
	if(mp[y-1][x+1] == 1){
		mp[y-1][x+1] = 2;
		func(y-1,x+1);
	}
}
void findL(){
	nx = -1;ny = -1;
	for(int i = 0; i < H; i++){
		for(int j = 0; j < W; j++){
			if(mp[i][j] == 1){
				nx = j,ny = i;
				//cout <<nx<<ny<<endl;
				i = H; j = W;
			}
		}
	}
}
int main(){
	
	cin >> H>>W;
	while(W!=0){
		for(int i = 0; i < H; i++){
			for(int j = 0; j < W; j++){
				cin >> mp[i][j];
			}
		}
		int c = 0;
		findL();
		while(nx != -1 && ny != -1){
			func(ny,nx);
			c++;
			findL();
		}
		cout << c << endl;
		cin >> W >> H;
	}
	return 0;
}

C++: #include <stdio.h>
#include <algorithm>
#include <vector>
#include <queue>
#include <memory.h>
#include <functional>

using namespace std;

//FILE * in = freopen("B", "r", stdin);

typedef pair<int,int> P;

int n, m;
int cnt = 0;
int data[100][100];
int check[100][100];

int mvx[] = {-1, 0, 1, -1, 1, -1, 0, 1};
int mvy[] = {-1, -1, -1, 0, 0, 1, 1, 1};

void input() {
	for(int i = 0; i < m; i++){
		for(int j = 0; j < n; j++) {
			scanf("%d", &data[i][j]);
		}
	}
	cnt = 0;
	memset(check, 0, sizeof(check));
}

void bfs(int x, int y) {
	queue<P> que;
	que.push(P(x,y));
	check[x][y] = 1;
	while(!que.empty()){
		P cur = que.front(); que.pop();
		for(int i = 0; i < 8; i++) {
			if(cur.first + mvx[i] >= 0 && cur.first + mvx[i] < n && cur.second + mvy[i] >= 0 && cur.second + mvy[i] < m
				&& data[cur.first + mvx[i]][cur.second + mvy[i]] && !check[cur.first+mvx[i]][cur.second+mvy[i]]){
					check[cur.first +mvx[i]][cur.second+mvy[i]] = 1;
					que.push(P(cur.first+mvx[i], cur.second+mvy[i]));
			}
		}
	}
}

void process() {
	for(int i = 0; i < n; i++) {
		for(int j = 0; j < m; j++) {
			if(data[i][j] && !check[i][j]) {
				bfs(i,j);
				++cnt;
			}
		}
	}
	printf("%d\n", cnt);
}

int main() {
	while(true) {
		scanf("%d%d", &n, &m);
		if(n == 0) break;
		input();
		process();
	}
	return 0;
}

C++: #include<cstdio>
#include<utility>
#include<algorithm>
#include<set>
using namespace std;

int w,h;
pair<int,int> g[50][50];
int s[50][51];

void dfs(int x,int y,int xx,int yy){
    g[x][y]=make_pair(xx,yy);
    for(int i=max(0,x-1);i<min(x+2,h);i++){
        for(int j=max(0,y-1);j<min(y+2,w);j++){
            if(s[i][j]&&(g[i][j].first!=xx||g[i][j].second!=yy)){
                dfs(i,j,xx,yy);
            }
        }
    }
}

int main(){
    scanf("%d%d",&w,&h);
    while(w&&h){
        for(int i=0;i<h;i++){
            for(int j=0;j<w;j++){
                scanf("%d",&s[i][j]);
            }
        }
        for(int i=0;i<h;i++){
            for(int j=0;j<w;j++){
                g[i][j]=make_pair(i,j);
            }
        }
        for(int i=0;i<h;i++){
            for(int j=0;j<w;j++){
                if(s[i][j]==1&&g[i][j].first==i&&g[i][j].second==j){
                    dfs(i,j,i,j);
                }
            }
        }
        set<pair<int,int> > se;
        for(int i=0;i<h;i++){
            for(int j=0;j<w;j++){
                if(s[i][j]==1){
                    se.insert(g[i][j]);
                }
            }
        }
        printf("%ld\n",se.size());
        scanf("%d %d",&w,&h);
    }
}