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>
#include <cstdio>
#include <queue>

using namespace std;

typedef pair<int, int> p;

int t_x[] = {1, 1, 1, 0, -1, -1, -1, 0};
int t_y[] = {1, 0, -1, -1, -1, 0, 1, 1};

int field[52][52];  

int main()
{
  while (true) {
    memset(field, 0, sizeof field);
    int width, height;
    scanf("%d %d", &width, &height);
    
    if (width == 0 && height == 0) break;
    
    for (int i = 1; i <= height; i++) {
      for (int j = 1; j <= width; j++) {
	scanf(" %d", &field[i][j]);
      }
    }
    
    queue<p> que;
    int c = 0;

    for (int i = 1; i <= height; i++) {
      for (int j = 1; j <= width; j++) {
	if (field[i][j] == 1) {
	  c++;
	  que.push(p(i, j));
	  field[i][j] = 0;
	  while (!que.empty()) {
	    p tmp = que.front();
	    que.pop();
	    //field[tmp.second][tmp.first] = 0;
	    //cout << tmp.first << ", " << tmp.second << endl;
	    for (int k = 0; k < 8; k++) {
	      int tx = tmp.second + t_x[k];
	      int ty = tmp.first + t_y[k];
	      //cout << ty << ", "<< tx << " =  "<< field[ty][tx] << endl;
	      if (field[ty][tx] == 1) {
		field[ty][tx] = 0;
		que.push(p(ty, tx));
	      }
	    }
	    //cout << endl;
	    //cout << i << " " << j << endl;
	    for (int k = 1; k <= height; k++) {
	      for (int l = 1; l <= width; l++) {
		//cout << field[k][l] << " ";
	      }
	      //cout << endl;
	    }
	    //cout << endl;
	  }
	}
      }     
    }
    cout << c << endl;
  }
  return 0;
}

C++: #include <cstdio>

int w, h;
int c[50][50];

void dfs(int a, int b){
	for(int i = 0; i < 3; i++){
		for(int j = 0; j < 3; j++){
			int A = a+i-1, B = b+j-1;
			if(0<=A&&A<w&&0<=B&&B<h&&c[A][B]){
				c[A][B] = 0;
				dfs(A,B);
			}
		}
	}
}

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

C++: /*
URL: http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=1160&lang=jp
?????????: How Many Islands?
?????°:
18:49 ?????????????????????????§£?????????
*/
#include <iostream>
using namespace std;

int dat[52][52]; // ??¨?????????1???????????£?????°

void delete_island_from(int i, int j)
{
	int dx[8] = {-1,-1,-1, 0,  0, 1, 1, 1};
	int dy[8] = {-1, 0, 1,-1,  1,-1, 0, 1};

	dat[i][j] = 0;
	for(int k=0;k<8;k++) {
		if(dat[i+dx[k]][j+dy[k]]) {
			delete_island_from(i+dx[k],j+dy[k]);
		}
	}
}


int main()
{
	while(true){ // data set
		//dat???0????????¢
		for(int i=0;i<52;i++){
			for(int j=0;j<52;j++){
				dat[i][j]=0;
			}
		}

		int w; int h;
		cin >> w >> h;
		if(w == 0 && h == 0) {break;}

		for(int i=0; i<h;i++) {
			for(int j=0;j<w;j++) {
				cin >> dat[i+1][j+1]; // ??¨?????????1???????????£?????°
			}
		}

		int ans = 0;
		while(true) {
			for(int i=0; i<h+2;i++) { // ????????£?????°??????
				for(int j=0;j<w+2;j++) {
					if(dat[i][j] == 1){
						delete_island_from(i,j);
						ans++;
						goto label1;
					}
				}
			} // all is ocean
			cout << ans << endl;
			break;


			label1: ;
		}
	}
}