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>

using namespace std;

#define rep(i, n) REP(i, 0, n)
#define REP(i,k,n) for(int i = k; i < n; i++)
#define mmax(start, end) *max_element(start, end)
#define mmin(start, end) *min_element(start, end)
#define argmax max_element
#define argmin min_element
#define push push_back
#define pop pop_back
#define ALL(x) (x).begin(), (x).end()

typedef long long ll;
typedef string str;

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

template<class T = ll> T in() {
    T _in;
    cin >> _in;
    return _in;
}

int w, h;
bool c[55][55] = {};

void DFS(int y, int x) {
    c[y][x] = 0;
    rep(i, 8) {
        if(y+dy[i]<0 || y+dy[i]>=h || x+dx[i]<0 || x+dx[i]>=w) continue;
        if(c[y + dy[i]][x + dx[i]]) {
            DFS(y + dy[i], x + dx[i]);
        }
    }
}

int main(){
    cin.tie(0);
    ios::sync_with_stdio(false);

    while(cin >> w >> h,w){
        rep(i, h) {
            rep(j, w) {
                cin >> c[i][j];
            }
        }

        int ans = 0;
        // 探索
        rep(y, h) {
            rep(x, w) {
                if (c[y][x]) {
                    DFS(y, x);
                    ans++;
                }
            }
        }

        cout << ans << endl;
    };
    return 0;
}

C++: #include <iostream>
#include <iomanip>
#include <vector>
#include <string>
#include <stack>
#include <set>
#include <cmath>
#include <algorithm>
using namespace std;


int w , h;
int land[51][51];

void dfs(int px , int py){
	int tx , ty;
	land[py][px]=0;
	for(int i=-1 ; i<=1 ; ++i){
		for(int j=-1 ; j<=1 ; ++j){
			tx=px+i , ty=py+j;
			if(tx<0 || tx>=w || ty<0 || ty>=h) continue;
			if(land[ty][tx]) dfs(tx , ty);
		}
	}
}


int main(){
	int cnt=0;
	while(cin >> w >> h , w||h){
		for(int i=0 ; i< h ; ++i){
			for(int j=0 ; j< w ; ++j){
				cin >> land[i][j];
			}
		}
		for(int i=0 ; i<h ; ++i){
			for(int j=0 ; j<w ; ++j){
				if(land[i][j]){
					dfs( j , i);
					cnt++;
				}
			}
		}
		cout << cnt << endl;
		cnt=0;
	}
	return 0; 
}

C++: #include"bits/stdc++.h"

#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define REP(i, n) for (int i = 1; i <= (int)(n); i++)
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
using namespace std;


vector<string>road;
int ix[] = { 0,1,1,1,0,-1,-1,-1 };
int iy[] = { -1,-1,0,1,1,1,0,-1 };
void dfs(int y, int x, int h, int w) {
	road[y][x] = '0';
	rep(i, 8) {
		int dx = x + ix[i], dy = y + iy[i];
		if (dx < 0 || w <= dx || dy < 0 || h <= dy || road[dy][dx] == '0')continue;
		dfs(dy, dx, h, w);
	}
}

int main() {
	while (1) {
		int h, w, cnt = 0;
		string k;
		cin >> w >> h;
		if (h == 0 || w == 0)break;
		road.resize(h);
		road.assign(h, "");
		rep(i, h)rep(j, w) {
			cin >> k;
			road[i] += k;
		}
		rep(i, h)rep(j, w) {
			if (road[i][j] == '0')continue;
			dfs(i, j, h, w);
			cnt++;
		}
		cout << cnt << endl;
	}
	return 0;
}

C++: #include <math.h>

#include <algorithm>
#include <bitset>
#include <iostream>
#include <sstream>
#include <vector>

using namespace std;

void dfs(int x, int y, vector<vector<int>>& field) {
  if (0 <= x && x < field.size() && 0 <= y && y < field[0].size()) {
    if (field[x][y] == 0) {
      return;
    }
  } else {
    return;
  }

  field[x][y] = 0;
  for (int dx = -1; dx <= 1; dx++) {
    for (int dy = -1; dy <= 1; dy++) {
      dfs(x + dx, y + dy, field);
    }
  }
  return;
}

int main() {
  vector<int> ans_v;
  for (int k = 0; k < 100; k++) {
    int w, h;
    cin >> w >> h;
    if (w == 0) {
      break;
    }

    vector<vector<int>> field(h, vector<int>(w));
    for (int i = 0; i < h; i++) {
      for (int j = 0; j < w; j++) {
        cin >> field[i][j];
      }
    }
    int ans = 0;
    for (int i = 0; i < h; i++) {
      for (int j = 0; j < w; j++) {
        if (field[i][j] == 1) {
          dfs(i, j, field);
          ans++;
        }
      }
    }

    ans_v.push_back(ans);
  }

  for (int i = 0; i < ans_v.size(); i++) {
    cout << ans_v[i] << endl;
  }

  return 0;
}