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;
typedef long long ll;
const double EPS=1e-10;
const ll INF=1000000000;
int w,h;
int c[60][60];
bool visited[60][60];
int dx[8]={0,1,0,-1,1,-1,1,-1};
int dy[8]={1,0,-1,0,1,1,-1,-1};
bool field(int x,int y){
    if(x>=0&&x<w&&y>=0&&y<h){
        return true;
    }
    return false;
}
int dfs(int x,int y){
    if(visited[y][x]){
        return 0;
    }
    visited[y][x]=true;
    for(int i=0;i<8;i++){
        int nx=x+dx[i];
        int ny=y+dy[i];
        if(field(nx,ny)&&c[ny][nx]){
            dfs(nx,ny);
        }
    }
    return 1;
}
int main(){
    while(cin>>w>>h,w+h){
        memset(visited,false,sizeof(visited));
        for(int i=0;i<h;i++){
            for(int j=0;j<w;j++){
                cin>>c[i][j];
            }
        }
        int ans=0;
        for(int i=0;i<h;i++){
            for(int j=0;j<w;j++){
                if(c[i][j]){
                    ans+=dfs(j,i);
                }
            }
        }
        cout<<ans<<endl;
    }
    return 0;
}

C++: #include <cmath>
#include<iostream>
#include<vector>
#include<algorithm>
#include<functional>
#include<queue>
#include<set>
#include<tuple>
#include<bitset>
#include<iomanip>
using namespace std;
typedef long long ll;
typedef pair<ll, ll> P;
ll inf = 1000000007;
int dx[8] = { 1,-1,0,0,-1,-1,1,1 };
int dy[8] = { 0,0,1,-1,-1,1,-1,1 };
int dif[55][55];
char c[55][55];
int h, w;
void dfs(P p) {
	queue<P>que;
	que.push(p);
	while (!que.empty()) {
		int nowy = que.front().first;
		int nowx = que.front().second;
		que.pop();
		for (int i = 0; i < 8; i++) {
			int newy = nowy + dy[i];
			int newx = nowx + dx[i];
			if (newy >= 0 && newy < h && newx >= 0 && newx < w && dif[newy][newx] == inf && c[newy][newx] == '1') {
				dif[newy][newx] = 1;
				que.push(make_pair(newy, newx));
			}
		}

	}
	
}

int main() {
	vector<ll>ans;
	while (1) {
		
		ll count = 0;
		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];
				dif[i][j] = inf;
			}
		}
		
		for (int i = 0; i < h; i++) {
			for (int j = 0; j < w; j++) {
				if (dif[i][j] == inf&&c[i][j]=='1') {
					count++;
					dif[i][j] = 1;
					dfs(make_pair(i, j));
				}
			}
		}
		ans.push_back(count);
	}
	for (int i = 0; i < ans.size(); i++) {
		cout << ans[i] << endl;
	}
	return 0;
}

C++: #include<bits//stdc++.h>
using namespace std;
int sum;
void solve(bool a[50][50],int h, int w, int i, int j){
	for(int z=-1;z<2;z++){
		for(int x=-1;x<2;x++){
			if(i+z>=0&&i+z<h&&j+x>=0&&j+x<w&&a[i+z][j+x]){
				a[i+z][j+x]=false;
				solve(a,h,w,i+z,j+x);
			}
		}
	}
}
int main(){
	int h,w;
	while(cin>>w>>h&&h!=0&&w!=0){
		bool a[50][50];
		for(int i=0;i<h;i++){
			for(int j=0;j<w;j++){
				int x;
				cin>>x;
				if(x==0) a[i][j]=false;
				else a[i][j]=true;
			}
		}
		sum=0;
		for(int i=0;i<h;i++){
			for(int j=0;j<w;j++){
				if(a[i][j]){
					sum++;
					solve(a,h,w,i,j);
				}
			}
		}
		cout<<sum<<endl;
	}
}

C++: #include <stdio.h>

void dps(int il[50][50], int y, int x)	{
	il[y][x] = 0;
	
	for (int dy = -1; dy <= 1; dy++)	{
		for (int dx = -1; dx <= 1; dx++)	{
			if (dy == 0 && dx == 0)	continue;
			if (y+dy < 0 || y+dy >= 50 || x+dx < 0 || x+dx >= 50)	continue;
			if (il[y+dy][x+dx] == 1)	dps(il, y+dy, x+dx);
		}
	}
}

int main()	{
	
	int w, h, cnt;
	int il[50][50];
	
	while (true)	{
		
		scanf("%d %d", &w, &h);
		if (w == 0)	break;
		
		cnt = 0;
		
		for (int y = 0; y < 50; y++)	{
			for (int x = 0; x < 50; x++)	{
				il[y][x] = 0;
			}
		}
		
		for (int y = 0; y < h; y++)	{
			for (int x = 0; x < w; x++)	{
				scanf("%d", &il[y][x]);
			}
		}
		
		for (int y = 0; y < h; y++)	{
			for (int x = 0; x < w; x++)	{
				if (il[y][x] == 1)	{
					dps(il, y, x);
					cnt++;
				}
			}
		}
		
		printf("%d\n", cnt);
	}
	
	return 0;
}