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;
 
int main(void){
    while (1) {
        int Y, X;
        int c[55][55];
        cin >> X >> Y;
         
        //終了
        if (Y == 0 && X == 0) break;
         
        for (int i = 1; i <= Y; i++) {
            for (int j = 1; j <= X; j++) cin >> c[i][j];
        }
         
        //深さ別にリストを作成
        int vy[2555][155], vx[2555][155], pl[2555];
        for (int i = 0; i < 2000; i++) {
            pl[i] = 0;
            vy[i][0] = vx[i][0] = -1;
            for (int j = 1; j <= 553; j++) {
                vy[i][j] = vx[i][j] = 0;
            }
        }  
 
        //移動方向の指定
        int dy[8] = {1, 0, -1, 0, 1, 1, -1, -1};
        int dx[8] = {0, 1, 0, -1, 1, -1, 1, -1};
     
        //通過済みかどうか
        bool psd[55][55];
        
        for (int i = 0; i <= 53; i++) {
            for (int j = 0; j <= 53; j++) psd[i][j] = false;
        }
        
        for (int i = 1; i <= Y; i++) {
            for (int j = 1; j <= X; j++) {
                psd[i][j] = true;
                if (c[i][j] == 0) psd[i][j] = false;
            }
        }
         
        for (int i = 0; i <= Y + 1; i++) psd[i][0] = psd[i][X + 1] = false;
        for (int i = 0; i <= X + 1; i++) psd[0][i] = psd[Y + 1][i] = false;
         
        bool fns = false;
        int isl = 0;
        while (1) {
            for (int inf = 0; true; inf++) {
                bool spot = false;
                if (inf == 0) {
                    vy[0][0] = -1;
                    for (int i = 1; i <= Y; i++) {
                        for (int j = 1; j <= X; j++) {
                            if (psd[i][j] == true) {
                                vy[0][0] = i;
                                vx[0][0] = j;
                                isl++;
                                pl[0] = 1;
                                psd[i][j] = false;
                                spot = true;
                                break;
                            }
                        }
                        if (spot) break;
                    }
                    if (vy[0][0] == -1) {
                        fns = true;
                        break; //4, 全部の島の確認終了
                    }
                }
                else {
                    int pt = 0;
                    for (int i = 0; i < pl[inf - 1]; i++) {
                        for (int dir = 0; dir < 8; dir++) {
                            
                            if (vy[inf - 1][i] + dy[dir] != -1 && vy[inf - 1][i] + dy[dir] != Y + 2 && vx[inf - 1][i] + dx[dir] != -1 && vx[inf - 1][i] + dx[dir] != X + 2) {
                                if (psd[vy[inf - 1][i] + dy[dir]][vx[inf - 1][i] + dx[dir]] == true) {
                                    vy[inf][pt] = vy[inf - 1][i] + dy[dir];
                                    vx[inf][pt] = vx[inf - 1][i] + dx[dir];
                                    pl[inf]++;
                                    psd[vy[inf][pt]][vx[inf][pt]] = false;
                                    pt++;
                                }
                            }
                        }
                    }
                    if (pt == 0) break; //4, 1つの島の確認終了
                }
//                cout << "*" << inf << endl;
//                for (int i = 0; i < pl[inf]; i++) cout << vy[inf][i] << ", " << vx[inf][i] << endl;
            }
            if (fns) {
                cout << isl << endl;
                break; // 2, query終了
            }
        }
    }
}

C++: #include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ull = unsigned long long;
#define REP(i,a) for(int i=0;i<(a);i++)
#define MOD 1000000007

int main(){
  while(1){
    int h,w;
    cin>>w>>h;
    if(h==0&&w==0) break;
    int a[h][w];
    bool used[h][w];
    for(int i=0;i<h;i++){
      for(int j=0;j<w;j++){
        cin>>a[i][j];
        used[i][j]=0;
      }
    }
    int ans=0;
    queue<pair<int,int>> q;
    for(int i=0;i<h;i++){
      for(int j=0;j<w;j++){
        if(a[i][j]&&!used[i][j]){
          //cout<<i<<" "<<j<<endl;
          ans++;
          q.push(make_pair(i,j));
          while(!q.empty()){
            pair<int,int> p=q.front();
            q.pop();
            int x=p.first, y=p.second;
            if(used[x][y]) continue;
            used[x][y]=1;
            for(int i=-1;i<2;i++){
              for(int j=-1;j<2;j++){
                if(x+i==-1||x+i==h) continue;
                if(y+j==-1||y+j==w) continue;
                if(a[x+i][y+j]&&!used[x+i][y+j]){
                  q.push(make_pair(x+i,y+j));
                }
              }
            }
          }
        }
      }
    }
    cout<<ans<<endl;
  }
  return 0;
}