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++: #if 0
20分

#endif
#include <iostream>
#include <memory>
#include <vector>
#include <string>
#include <algorithm>
#include <assert.h>
#include <complex>
#include <queue>
#define rep(i,n) for(int i=0, i##_len=(n); i<i##_len; ++i)
using namespace std;
using ll = long long;
ll ll_max = numeric_limits<ll>::max();
ll ll_min = numeric_limits<ll>::min();
int int_max = numeric_limits<int>::max();
int int_min = numeric_limits<int>::min();
int W, H;
int islands[50][50];
queue<pair<int, int> > now;
vector<pair<int, int> > not_reached;
int dirs[8][2] = {{-1, 0}, {0, -1}, {1, 0}, {0, 1}, {1, -1}, {1, 1}, {-1, 1}, {-1, -1}};
bool check_point(pair<int, int> point) {
    bool ret = true;
    ret &= point.first > -1;
    ret &= point.second > -1;
    ret &= point.first < H;
    ret &= point.second < W;
    ret &= islands[point.first][point.second] == 1;
    return ret;
}
void bfs() {
    while (!now.empty()) {
        pair<int, int> start = now.front();
        now.pop();
        for (auto dir : dirs) {
            auto next = make_pair(start.first + dir[0], start.second + dir[1]);
            if (check_point(next)) {
                // cout << "next:" << next.first << ", " << next.second << endl;
                now.push(next);
                auto next_it = find(not_reached.begin(), not_reached.end(), next);
                if (next_it != not_reached.end())
                    not_reached.erase(next_it);
                islands[next.first][next.second] = 2;
            }
        }
    }
}
int main(void){
    cin.tie(0);
    ios::sync_with_stdio(false);

    while (cin >> W >> H && W && H) {
        rep(h, H) {
            rep(w, W) {
                cin >> islands[h][w];
                if (islands[h][w] == 1)
                    not_reached.push_back(make_pair(h, w));
            }
        }
        int cnt = 0;
        while (!not_reached.empty()) {
            ++cnt;
            queue<pair<int, int> > empty;
            swap(now, empty);
            now.push(not_reached.back());
            not_reached.pop_back();
            bfs();
        }
        cout << cnt << endl;
    }

    return 0;
}

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

using namespace std;

using ll = long long;

int w, h;
vector< vector<int> > c, island;

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

void dfs(int x, int y, int id) {

    island[y][x] = id;

    for(int i = 0; i < 8; i++) {

        int nx = x + dx[i];
        int ny = y + dy[i];

        if(nx < 0 || nx >= w || ny < 0 || ny >= h)
            continue;

        if(c[ny][nx] == 1 && island[ny][nx] != id)
            dfs(nx, ny, id);

    }

}

int main(){

    cin.tie(0);
    ios::sync_with_stdio(false);

    int ans;

    while(cin >> w >> h && w) {

        c.assign(h, vector<int>(w));
        island.assign(h, vector<int>(w, -1));
        ans = 0;

        for(int y = 0; y < h; y++)
            for(int x = 0; x < w; x++)
                cin >> c[y][x];

        for(int x = 0; x < w; x++)
            for(int y = 0; y < h; y++)
                if(c[y][x] == 1 && island[y][x] == -1)
                    dfs(x, y, ans++);

        cout << ans << endl;

    }
}

C++: #include <bits/stdc++.h>
#define err(args...) {}
#ifdef DEBUG
#include "_debug.cpp"
#endif
using namespace std;
using ll = long long;
bool hori(int di, int dj) { return abs(di) == 0 and abs(dj) == 1; }
bool vert(int di, int dj) { return abs(di) == 1 and abs(dj) == 0; }
bool diag(int di, int dj) { return abs(di) == 1 and abs(dj) == 1; }
template <typename signature> using f = const function<signature>&;
void flood(vector<vector<int>>& a, f<bool(int, int)> can, f<void(int, int, int, int)> f) {
    int n = a.size() - 2, m = a[0].size() - 2;
    vector<vector<bool>> vis(n + 2, vector<bool>(m + 2));
    function<void(int, int, int, int)> dfs = [&](int i, int j, int from_i, int from_j) {
        if(a[i][j] and not vis[i][j]) {
            f(i, j, from_i, from_j);
            vis[i][j] = true;
            for(int di = -1; di <= 1; di++) {
                for(int dj = -1; dj <= 1; dj++) {
                    if(can(di, dj)) {
                        dfs(i + di, j + dj, i, j);
                    }
                }
            }
        }
    };
    for(int i = 1; i <= n; i++) {
        for(int j = 1; j <= m; j++) {
            if(not vis[i][j]) {
                dfs(i, j, 0, 0);
            }
        }
    }
}
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    int w, h;
    while(cin >> w >> h and w and h) {
        vector<vector<int>> a(h + 2, vector<int>(w + 2));
        for(int i = 1; i <= h; i++) {
            for(int j = 1; j <= w; j++) {
                cin >> a[i][j];
            }
        }
        int ans = 0;
        flood(a, [](int di, int dj) { return true; }, [&](int i, int j, int from, int) {
            ans += not from;
        });
        cout << ans << endl;
    }
    return 0;
}