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;
#define all(c) (c).begin(),(c).end()
#define rrep(i,n) for(int i=(int)(n)-1;i>=0;i--)
#define REP(i,m,n) for(int i=(int)(m);i<(int)(n);i++)
#define rep(i,n) REP(i,0,n)
#define iter(c) __typeof((c).begin())
#define tr(it,c) for(iter(c) it=(c).begin();it!=(c).end();it++)
#define pb(a) push_back(a)
#define pr(a) cout<<(a)<<endl
#define PR(a,b) cout<<(a)<<" "<<(b)<<endl
#define F first
#define S second
#define ll long long
bool check(int n,int m,int x,int y){return (x<0||x>=n||y<0||y>=m)?false:true;}
const ll MAX=1000000007,MAXL=1LL<<60,dx[4]={-1,0,1,0},dy[4]={0,-1,0,1};
typedef pair<int,int> P;

int n,m;
int a[51][51];
bool d[51][51];

void dfs(int nx, int ny) {
  d[nx][ny]=true;
  REP(i,-1,2) {
    REP(j,-1,2) {
      int x=nx+i,y=ny+j;
      if(check(n,m,x,y) && a[x][y] && !d[x][y]) dfs(x,y);
    }
  }
}

int main() {
  while(cin >> m >> n && (n||m)) {
    rep(i,n) {
      rep(j,m) cin >> a[i][j];
    }
    memset(d,false,sizeof(d));
    int cnt=0;
    rep(i,n) {
      rep(j,m) {
	if(!d[i][j] && a[i][j]) {
	  cnt++;
	  dfs(i,j);
	}
      }
    }
    pr(cnt);
  }
  return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;
#define OUT(x) cout<<x<<endl
#define DEBUG(x) cout<<#x<<": "<<x
const int BA = 1000;
const int INFTY = (1<<21);
int c[51][51];
int w,h;
int del(int x,int y){
  if(x<0)return 0;
  if(c[x][y]){
    c[x][y] = 0;
    return del(x+1,y)+del(x,y+1)+del(x+1,y+1)+del(x-1,y+1);
    
  }
  else return 0;
  
}
int solve(int x,int y){
  if(x==0 && y == h)return 0;
  else if(x==w){
    return solve(0,y+1);
  }
  else if(c[x][y]==1){
    del(x,y);
    return solve(x+1,y)+1;
  }
  else return solve(x+1,y);
}
int main(){
  while(cin>>w>>h&&w&&h){
    for(int i=0;i<h;i++){
      for(int j=0;j<w;j++){
	cin >> c[i][j];
      }
    }
    cout << solve(0,0) << endl;
  }
}

C++: #include<iostream>
using namespace std;

int w, h;
bool data[99][99]; //y,x

int solve(int x, int y){

  if(x < 0 || y < 0 || x == w || y == h) return 0;
  if(!data[y][x]) return 0;

  data[y][x] = false;

  for(int i=-1;i<2;i++) for(int j=-1;j<2;j++) solve(x+j, y+i);

  return 1;
}

int main(){

  while(true){
    cin >> w >> h;
    if(!w && !h) break;

    for(int i=0;i<h;i++) for(int j=0;j<w;j++) cin >> data[i][j];

    int ret = 0;
    for(int i=0;i<h;i++) for(int j=0;j<w;j++) if(data[i][j]) ret += solve(j, i);

    cout << ret << endl;
  }

}

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

struct UnionFind{
    vector<int> data;

    UnionFind(int N) : data(vector<int>(N,-1)){}

    int root(int x){
        if(data[x] < 0){
            return x;
        }else{
            return data[x] = root(data[x]);
        }
    }

    bool same(int x,int y){
        return root(x) == root(y);
    }

    void unite(int x,int y){
        if(!same(x,y)){
            x = root(x);
            y = root(y);
            if(data[x] < data[y]){
                data[x] += data[y];
                data[y] = x;
            }else{
                data[y] += data[x];
                data[x] = y;
            }
        }
        return;
    }

};

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

void solve(int w,int h){
    swap(w,h);
    int c[w][h];
    for(int i = 0;i < w;i++){
        for(int j = 0;j < h;j++){
            cin >> c[i][j];
        }
    }
    UnionFind uf(w*h);
    for(int i = 0;i < w;i++){
        for(int j = 0;j < h;j++){
            for(int k = 0;k < 8;k++){
                int x = i + dx[k];
                int y = j + dy[k];
                if(0 <= x && x < w && 0 <= y && y < h){
                    if(c[i][j] && c[x][y]){
                        uf.unite(i*h+j,x*h+y);
                    }
                }
            }
        }
    }
    set<int> s;
    for(int i = 0;i < w*h;i++)s.insert(uf.root(i));
    int ans = 0;
    for(auto x:s){
        ans += c[x/h][x%h];
    }
    cout << ans << endl;
}

int main(){
    int w,h;
    while(true){
        cin >> w >> h;
        if(!w && !h)return 0;
        solve(w,h);
    }
}

C++: #include<iostream>
#include<queue>
using namespace std;

struct mapst {
	int x, y;
};

#define func(x,y) (c[y][x]&&!f[y][x])

int main() {
	int w, h, ans=0;
	int c[52][52]={{0}}, f[52][52]={{1}};
	int dx[8] = {-1, -1, 0, 1, 1, 1, 0, -1};
	int dy[8] = {0, -1, -1, -1, 0, 1, 1, 1};
	queue<mapst> q;
	while(1) {
		cin >> w >> h;
		if(!w&&!h) break;
		ans = 0;
		for(int i=0; i<52; ++i) for(int j=0; j<52; ++j) {
			c[i][j] = 0;
			f[i][j] = 1;
		}
		for(int i=1; i<=h; ++i) for(int j=1; j<=w; ++j) {
			cin >> c[i][j];
			f[i][j] = 1-c[i][j];
		}
		for(int i=1; i<=h; ++i) for(int j=1; j<=w; ++j) {
			if(func(j,i)) {
				mapst m, ms;
				m.x = j; m.y = i;
				q.push(m);
				ans++;
				do {
					m = q.front();
					q.pop();
					f[m.y][m.x] = 1;
					for(int k=0; k<8; k++) {
						if(func(m.x+dx[k],m.y+dy[k])) {
							ms.x = m.x+dx[k]; ms.y = m.y+dy[k];
							q.push(ms);
						}
					}
				}while(!q.empty());
			}
		}
		cout << ans << endl;
	}
	return 0;
}