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 <fstream>
#include <cstdio>
#include <cmath>
#include <vector>
#include <string>
#include <set>
#include <map>
#include <stack>
#include <queue>
#include <deque>
#include <bitset>
#include <algorithm>
#include <complex>
#include <array>
#include <iomanip>
using namespace std;

#define REP(i,n) for(int i=0; i<n; ++i)
#define FOR(i,a,b) for(int i=a; i<=b; ++i)
#define FORR(i,a,b) for (int i=a; i>=b; --i)
#define ALL(c) (c).begin(), (c).end()

typedef long long ll;
typedef vector<int> VI;
typedef vector<ll> VL;
typedef vector<long double> VD;
typedef vector<VI> VVI;
typedef vector<VL> VVL;
typedef vector<VD> VVD;
typedef pair<int,int> P;
typedef pair<ll,ll> PL;

template<typename T> void chmin(T &a, T b) { if (a > b) a = b; }
template<typename T> void chmax(T &a, T b) { if (a < b) a = b; }

int in() { int x; scanf("%d", &x); return x; }
ll lin() { ll x; scanf("%lld", &x); return x; }
#define INF 1LL<<60

void dfs(int cur_x, int cur_y, vector<vector<int> >& c, vector< vector<bool> >& visited, int H, int W) {
    visited[cur_y][cur_x] = true;
    for(int dx=-1; dx<=1; dx++)
        for(int dy=-1; dy<=1; dy++)
            if(
            (dx !=0 || dy != 0)
            && (cur_x+dx>=0)
            && (cur_x+dx<W)
            && (cur_y+dy>=0)
            && (cur_y+dy<H)
            && c[cur_y+dy][cur_x+dx] == 1
            && !visited[cur_y+dy][cur_x+dx]) {
                dfs(cur_x+dx, cur_y+dy, c, visited, H, W);
            }
}

int main() {
    while(1) {
        int W, H;
        cin >> W >> H;
        if(W==0 && H==0) break;
        vector<vector<int> > c(H, vector<int>(W));
        vector<vector<bool> > visited(H, vector<bool>(W, false));
        REP(i, H)
            REP(j, W) cin >> c[i][j];

        int ans = 0;
        REP(i, H)
            REP(j, W)
                if(!visited[i][j] && c[i][j] == 1) {
                    ans++;
                    dfs(j, i, c, visited, H, W);
                }
        cout << ans << endl;
    }
    return 0;
}

C++: #include <bits/stdc++.h>
 
using namespace std;
typedef long long ll;
 
#define rep(i, n) for(int i=0; i<(n); ++i)

int w, h;
int c[51][51];
int island[51][51];
int ans;
int dx[] = {1, -1, 0, 0, 1, -1, 1, -1};
int dy[] = {0, 0, 1, -1, 1, -1, -1, 1};

void dfs(int y, int x, int id) {
    island[y][x] = id;
    rep(i, 8) {
        int nx = x+dx[i];
        int ny = y+dy[i];
        if(nx>=0 && nx<w && ny>=0 && ny<h &&
                c[ny][nx] == 1 && island[ny][nx] != id) {
            dfs(ny, nx, id);
        }
    }
}
    
int main(void){
    while(cin >> w >> h && w) {
        rep(y, h) rep(x, w) cin >> c[y][x];
        ans = 0;
        memset(island, -1, sizeof(island));
        rep(y, h) {
            rep(x, w) {
                if(c[y][x]==1 && island[y][x]==-1) {
                    dfs(y, x, ans);
                    ans++;
                }
            }
        }
        cout << ans << endl;
    }
}

C++: #include<iostream>
#include<queue>
#include<utility>
using namespace std;
void search(int, int);
int c[50][50] = {}, map[50][50] = {};
void mapDraw(int,int);
queue< pair<int, int> > q;
int w, h;

int main() {

	while (1) {
		
		//initialize
		int count = 0;
		for (int i = 0; i < 50; i++) {
			for (int j = 0; j < 50; j++) {
				c[i][j] = 0;
				map[i][j] = 0;
			}
		}


		cin >> w >> h;
		if (w == 0 && h == 0) break;
		//input
		for (int i = 0; i < h; i++) {
			for (int j = 0; j < w; j++) {
				cin >> c[i][j];
			}
		}

		//search
		//unresearched:0, land:2, sea:1
		for (int i = 0; i < h; i++) {
			for (int j = 0; j < w; j++) {
				if (map[i][j] == 0) {
					map[i][j] = c[i][j] + 1;
					if (c[i][j] == 1) {
						q.push(make_pair(i, j));
						count++;
					}
				}

				pair<int, int> cur = make_pair(i, j);
				while (!q.empty()) {
					cur = q.front();
					int x = cur.second;
					int y = cur.first;
					q.pop();

					//cerr << "( " << y << ", " << x << " )now"<< endl;

					for (int a = -1; a <= 1; a++) {
						for (int b = -1; b <= 1; b++) search(y + a, x + b);
					}
				}
			}
		}

		cout << count << endl;
	}


	return 0;
}

void search(int i, int j) {
	if (map[i][j] == 0) {
		map[i][j] = c[i][j] + 1;
		if (c[i][j] == 1) q.push(make_pair(i, j));
	}
	//mapDraw(w, h);
}

void mapDraw(int w, int h) {
	for (int i = 0; i < h; i++) {
		for (int j = 0; j < w; j++) {
			cerr << map[i][j];
		}
		cerr << endl;
	}
	cerr << endl;
}