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>
#include<unordered_map>
#include<unordered_set>
using namespace std;
using ld = long double;
template<class T>
using Table = vector<vector<T>>;

int dx8[8] = { -1,-1,-1, 0, 1, 1, 1, 0 };
int dy8[8] = { -1, 0, 1, 1, 1, 0,-1,-1 };

vector<vector<int>>as;
int w,h;

void check(int y, int x) {
    for (int i = 0; i < 8; ++i) {
        int nx = x + dx8[i];
        int ny = y + dy8[i];
        if (as[ny][nx]) {
            as[ny][nx] = 0;
            check(ny, nx);
        }
    }
}

int main() {
    while (1) {
        cin >> w >> h;
        if (!w)break;
        vector<vector<int>>as2(h+2);
        as = as2;
        for (int i = 0; i <= h+1; ++i) {
            as[i].emplace_back(0);
            if (i != 0 && i != h + 1) {
                for (int j = 0; j < w; ++j) {
                    int c; cin >> c;
                    as[i ].emplace_back(c);
                }
            }
            else {
                for (int j = 0; j < w; ++j) {
                    as[i].emplace_back(0);
                }
            }
            
            as[i].emplace_back(0);
        }
        int ans = 0;
        for (int i = 1; i <= h; ++i) {
            for (int j = 1; j <= w; ++j) {
                if (as[i][j]) {
                    ans++;
                    check(i, j);
                }
            }
        }
        cout << ans << endl;
    }
}

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

using namespace std;

#define all(c) ((c).begin()), ((c).end())
#define dump(c) cerr << "> " << #c << " = " << (c) << endl;
#define iter(c) __typeof((c).begin())
#define tr(i, c) for (iter(c) i = (c).begin(); i != (c).end(); i++)
#define REP(i, a, b) for (int i = a; i < (int)(b); i++)
#define rep(i, n) REP(i, 0, n)
#define mp make_pair
#define fst first
#define snd second
#define pb push_back

typedef long long ll;
typedef vector<int> vi;
typedef vector<double> vd;
typedef pair<int,int> pii;

const int INF = 1 << 29;
const double EPS = 1e-10;

int W, H;
int field[52][52];

void dfs(int x, int y) {
  field[y][x] = 0;

  REP(dx, -1, 2) REP(dy, -1, 2) {
    int tx = x + dx;
    int ty = y + dy;
    if (tx < 0 || tx >= W || ty < 0 || ty >= H) continue;
    if (field[ty][tx]) dfs(tx, ty);
  }
}

int main() {
  for(; cin >> W >> H, (W | H) != 0; ) {

    rep(i, H) rep(j, W) cin >> field[i][j];

    int ans = 0;
    rep(i, H) rep(j, W) if (field[i][j]) {
      dfs(j, i);
      ans++;
    }

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

C++: #include <bits/stdc++.h>
using namespace std;
using ll=long long;
typedef pair<int,int> P;
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
int w,h;
int nx,ny;
void dfs(vector<vector<int>> &G,int a,int b){
    G.at(a).at(b)=0;
    
    for(int k=-1;k<=1;k++){
        for(int l=-1;l<=1;l++){
            nx=a+k;
            ny=b+l;
        if(0<=nx&& nx<h && 0<=ny&& ny<w && G.at(nx).at(ny)==1) dfs(G,nx,ny);
        }
    }
    return ;
}



int main(){
    int w,h;
    cin>>w>>h;
    vector<vector<int>>G(h,vector<int>(w));
    for(int i=0;i<h;i++){
        for(int j=0;j<w;j++){
            cin>>G.at(i).at(j);
        }
    }
    int count=0;
    for(int i=0;i<h;i++){
        for(int j=0;j<w;j++){
            if(G.at(i).at(j)==1){
                dfs(G,i,j);
                count++;
            }
        }
    }
cout<<count<<endl;
}

C++: #include<bits/stdc++.h>
using namespace std;
#define int long long
typedef pair<int,int> P;
signed main(){
  int w,h;
  while(cin>>w>>h,w||h){
    int c[h][w];
    for(int i=0;i<h;i++)
      for(int j=0;j<w;j++)
	cin>>c[i][j];
    int ans=0;
    int ax[]={-1,0,1,-1,1,-1,0,1};
    int ay[]={-1,-1,-1,0,0,1,1,1};
    int used[h][w];
    memset(used,0,sizeof(used));
    for(int i=0;i<h;i++){
      for(int j=0;j<w;j++){
	if(used[i][j]) continue;
	if(!c[i][j]) continue;
	ans++;
	queue<P> q;
	q.push(P(i,j));
	while(!q.empty()){
	  P p=q.front();q.pop();
	  int y=p.first,x=p.second;
	  //cout<<y<<" "<<x<<endl;
	  if(used[y][x]) continue;
	  if(!c[y][x]) continue;
	  used[y][x]=1;
	  for(int k=0;k<8;k++){
	    int ny=y+ay[k],nx=x+ax[k];
	    if(ny<0||ny>=h||nx<0||nx>=w) continue;
	    if(used[ny][nx]) continue;
	    if(!c[ny][nx]) continue;
	    q.push(P(ny,nx));
	  }
	}
      }
    }
    cout<<ans<<endl;
  }
  return 0;
}