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;
#define rep(i, n) for(ll i = 0, i##_len = (n); i < i##_len; i++)
#define reps(i, s, n) for(ll i = (s), i##_len = (n); i < i##_len; i++)
#define rrep(i, n) for(ll i = (n) - 1; i >= 0; i--)
#define rreps(i, e, n) for(ll i = (n) - 1; i >= (e); i--)
#define all(x) (x).begin(), (x).end()
#define sz(x) ((ll)(x).size())
#define len(x) ((ll)(x).length())

const ll d[8][2] = {{0, -1}, {1, -1}, {1, 0}, {1, 1}, {0, 1}, {-1, 1}, {-1, 0}, {-1, -1}};

void dfs(const vector<vector<ll>> &c, vector<vector<ll>> &g, ll x, ll y, ll root) {
    if (g[y][x] != -1) return;
    if (c[y][x] == 0) return;
    g[y][x] = root;
    rep(i, 8) {
        ll nx = x + d[i][0];
        ll ny = y + d[i][1];
        if ((nx < 0) || (nx >= sz(c[0])) || (ny < 0) || (ny >= sz(c))) continue;
        dfs(c, g, nx, ny, root);
    }
}

void solve(ll w, ll h) {
    vector<vector<ll>> c(h, vector<ll>(w)), g(h, vector<ll>(w, -1));
    rep(i, h) rep(j, w) cin >> c[i][j];
    set<ll> s;
    rep(i, h) {
        rep(j, w) {
            dfs(c, g, j, i, i * w + j);
            if (g[i][j] >= 0) s.insert(g[i][j]);
        }
    }
    cout << sz(s) << endl;
}

int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);
    // ifstream in("input.txt");
    // cin.rdbuf(in.rdbuf());
    while(true) {
        ll w, h;
        cin >> w >> h;
        if ((w == 0) && (h == 0)) break;
        solve(w, h);
    }
    return 0;
}

C++: #include <iostream>
#include <string>
#include <vector>
#include <cstdlib>
#include <cstdio>
#include <cmath>
#include <algorithm>
#include <map>
#include <stack>
#include <queue>
#include <set>
#include <cstring>

using namespace std;
// ascending order
#define vsort(v) sort(v.begin(), v.end())
// descending order
#define vsort_r(v) sort(v.begin(), v.end(), greater<int>())
#define vunique(v) v.erase(unique(v.begin(), v.end()), v.end())
#define mp make_pair
#define ts(x) to_string(x)
#define rep(i, a, b) for(int i = (int)a; i < (int)b; i++)
#define repm(i, a, b) for(int i = (int)a; i > (int)b; i--)
#define bit(a) bitset<8>(a)
#define des_priority_queue priority_queue<int, vector<int>, greater<int> >
typedef long long ll;
typedef pair<int, int> P;
const ll INF = 1e18;

#define MAX_V 1000000

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

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

  vector<int> ans;
  while(true) {
      int w, h;
      cin >> w >> h;
      if(w == 0 && h == 0) break;

      int c[h][w];
      bool reached[h][w];
      rep(i, 0, h) rep(j, 0, w) {
          cin >> c[i][j];
          reached[i][j] = false;
      }

      int rsl = 0;
      rep(y, 0, h) {
          rep(x, 0, w) {
              if(c[y][x] == 0) continue;
              if(reached[y][x]) continue;

              rsl++;
              stack<pair<int, int> > s;
              s.push(make_pair(x, y));
              reached[y][x] = true;
              while(!s.empty()) {
                  pair<int, int> p = s.top();
                  s.pop();
                  rep(i, 0, 8) {
                      int nx = p.first + dx[i], ny = p.second + dy[i];
                      if(!(0 <= nx && nx < w && 0 <= ny && ny < h)) continue;
                      if(c[ny][nx] == 0) continue;
                      if(reached[ny][nx]) continue;

                      reached[ny][nx] = true;
                      s.push(make_pair(nx, ny));
                  }
              }
          }
      }
      ans.push_back(rsl);
  }
  rep(i, 0, ans.size()) cout << ans[i] << endl;

}

C++: #include <bits/stdc++.h>
using namespace std;

int x,y;
const int mx[8]={-1,-1,-1,0,0,1,1,1};
const int my[8]={-1,0,1,-1,1,-1,0,1};

void dfs(vector<vector<int>> &c,int H,int W,int& h,int& w)
{
c[H][W] = 0;
for(int i=0;i<8;i++){y=H+my[i],x=W+mx[i];if(y<0||y>h-1||x<0||x>w-1)continue;if(!c[y][x])continue;dfs(c,y,x,h,w);}
}

int main()
{
int w,h,ans;
vector<vector<int>> c(50,vector<int>(50));
scanf("%d%d", &w, &h);
while(w!=0&&h!=0)
{
ans=0;
for(int i=0;i<h;i++)for(int j=0;j<w;j++)scanf("%d", &c[i][j]);
for(int i=0;i<h;i++)for(int j=0;j<w;j++){if(!c[i][j])continue;dfs(c,i,j,h,w);ans++;}
printf("%d\n",ans);
scanf("%d%d", &w, &h);
}
return 0;
}