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>
#include<queue>
#include<cstring>
using namespace std;
int x[50][50], col[50][50], h, w, c, i, j, k, l, p, q;
queue<int>Q, R;
int main() {
	while (true) {
		c = 0;
		memset(col, 0, sizeof(col));
		cin >> h >> w;
		if (h == 0) { break; }
		for (i = 0; i < h; i++) { for (j = 0; j < w; j++) { cin >> x[i][j]; } }
		for (i = 0; i < 50; i++) {
			for (j = 0; j < 50; j++) {
				if (x[i][j] == 1 && col[i][j] == 0) {
					c++;
					col[i][j] = c;
					Q.push(i * 100 + j);
					while (!Q.empty()) {
						while (!Q.empty()) {
							p = Q.front() / 100;
							q = Q.front() % 100;
							for (k = -1; k < 2; k++) {
								for (l = -1; l < 2; l++) {
									if (x[p + k][q + l] == 1 && col[p + k][q + l] == 0) {
										col[p + k][q + l] = c;
										R.push((p + k) * 100 + q + l);
									}
								}
							}
							Q.pop();
						}
						while (!R.empty()) {
							Q.push(R.front());
							R.pop();
						}
					}
				}
			}
		}
		cout << c << endl;
	}
}

C++: #include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <queue>
#include <string>
#include <map>
#include <set>
#include <stack>
#include <tuple>
#include <deque>
#include <numeric>
#include <bitset>
#include <iomanip>
#include <cassert>
#include <chrono>
#include <random>
#include <limits>
#include <iterator>
#include <functional>
#include <sstream>
#include <complex>
using namespace std;

using ll = long long;
using ull = uint64_t;
using P = pair<int, int>;
constexpr double EPS = 1e-9;
constexpr int INF = 1001001001;
constexpr int mod = 1000000007;
// constexpr int mod = 998244353;

template<class T>
inline bool chmax(T& x, T y){
    if(x < y){
        x = y;
        return true;
    }
    return false;
}
template<class T>
inline bool chmin(T& x, T y){
    if(x > y){
        x = y;
        return true;
    }
    return false;
}

constexpr int dx[8] = {1, 1, 0, -1, -1, -1, 0, 1};
constexpr int dy[8] = {0, 1, 1, 1, 0, -1, -1, -1};

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    for(;;){
        int R, C;
        cin >> R >> C;
        if(R == 0 && C == 0)    return 0;
        vector<vector<int>> c(C, vector<int>(R));
        for(int i = 0; i < C; ++i){
            for(int j = 0; j < R; ++j){
                cin >> c[i][j];
            }
        }
        vector<vector<bool>> used(C, vector<bool>(R, false));
        auto dfs = [&](auto&& self, int x, int y) -> void {
            used[x][y] = true;
            for(int i = 0; i < 8; ++i){
                int nx = x + dx[i], ny = y + dy[i];
                if(nx < 0 || nx >= C || ny < 0 || ny >= R)  continue;
                if(used[nx][ny] || c[nx][ny] == 0)  continue;
                self(self, nx, ny);
            }
            return;
        };
        int ans = 0;
        for(int i = 0; i < C; ++i){
            for(int j = 0; j < R; ++j){
                if(used[i][j] || c[i][j] == 0)  continue;
                ++ans;
                dfs(dfs, i, j);
            }
        }
        cout << ans << '\n';
    }
}

C++: #include<iostream>
#include<queue>
#include<utility>
using namespace std;

int W,H;
int c[51][51]={0};
int d[51][51]={0};
int island=0;

bool valid(pair<int,int> a){
    return (a.first>=1 && a.first<=W && a.second>=1 && a.second<=H);
}

template<typename A, size_t N, typename T>
void Fill(A (&array)[N], const T &val){
    std::fill( (T*)array, (T*)(array+N), val );
}

void bfs(pair<int,int> s){
    queue<pair<int,int>> Q;

    if(c[s.first][s.second]==1 && d[s.first][s.second]==0 && valid(s)){
        Q.push(s);
        d[s.first][s.second]=1;
        ++island;

        while(!Q.empty()){
            pair<int,int> cur=Q.front();
            Q.pop();

            for(int i=-1;i<=1;++i){
                for(int j=-1;j<=1;++j){
                    pair<int,int> dst=make_pair(cur.first+i,cur.second+j);

                    if(d[dst.first][dst.second]==0 && c[dst.first][dst.second]==1 && valid(dst)){
                        Q.push(dst);
                        d[dst.first][dst.second]=1;
                    }
                }
            }
        }
    }
}

int main(){
    
    while(cin>>W>>H && W!=0){
        for(int i=1;i<=H;++i){
            for(int j=1;j<=W;++j){
                cin>>c[j][i];
            }
        }

        for(int i=1;i<=W;++i){
            for(int j=1;j<=H;++j){
                pair<int,int> start=make_pair(i,j);
                bfs(start);
            }
        }
        cout<<island<<"\n";
        island=0;
        Fill(c,0);
        Fill(d,0);
    }
}