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;

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

void Dfs(int i, int j) {
  c[i][j] = 0;
  for (int di = -1; di <= 1; ++di) {
    for (int dj = -1; dj <= 1; ++dj) {
      if (di == 0 && dj == 0)
        continue;

      int ni = i + di, nj = j + dj;
      if (ni < 0 || ni >= h || nj < 0 || nj >= w) continue;
      if (c[ni][nj]) Dfs(ni, nj);
    }
  }
}

int main() {
  while (true) {
    cin >> w >> h;

    if (w == 0 && h == 0)
      break;

    c.resize(h, vector<int>(w));
    for (int i = 0; i < h; ++i)
      for (int j = 0; j < w; ++j)
        cin >> c[i][j];

    int ans = 0;
    for (int i = 0; i < h; ++i) {
      for (int j = 0; j < w; ++j) {
        if (c[i][j]) {
          Dfs(i, j);
          ++ans;
        }
      }
    }
    c.clear();

    cout << ans << endl;
  }
}

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

using namespace std;

typedef long long ll;
typedef vector<int> VI;

#define FOR(i,n) for(int (i)=0;(i)<(n);(i)++)
#define FOR1(i,n) for(int (i)=1;(i)<(n);(i)++)
#define eFOR(i,n) for(int (i)=0;(i)<=(n);(i)++)
#define eFOR1(i,n) for(int (i)=1;(i)<=(n);(i)++)
#define SORT(i) sort((i).begin(),(i).end())
constexpr auto INF = 1000000000;
constexpr auto LLINF = 9223372036854775807;
constexpr auto mod = 1000000007;

int w, h, c[50][50];
int dx[8] = { -1,0,1,-1,1,-1,0,1 }, dy[8] = { -1,-1,-1,0,0,1,1,1 };
void search(int x, int y) {
	if (x >= 0 && x < w && y >= 0 && y < h) {
		if (c[y][x] == 1) {
			c[y][x] = 0;
			FOR(k, 8)search(x + dx[k], y + dy[k]);
		}
	}
}

int main() {
	while (1) {
		cin >> w >> h;
		if (w == 0 && h == 0)break;
		FOR(i, h)FOR(j, w)cin >> c[i][j];
		int cnt = 0;
		FOR(i, h)FOR(j, w)if (c[i][j] == 1) {
			search(j, i);
			cnt++;
		}
		cout <<"   "<< cnt << endl;
	}
	

	return 0;
}

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

#define int long long

int w, h;
int field[51][51];

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

void dfs(int x, int y) {
    field[x][y] = 0;
    for(int i=0; i<8; ++i) {
        int nx = x + dx[i];
        int ny = y + dy[i];
        if(nx>=0&&nx<h&&ny>=0&&ny<w&&field[nx][ny]==1) dfs(nx, ny);
    }
}

signed main()
{
    while(cin>>w>>h, w) {
        for(int i=0; i<h; ++i)
            for(int j=0; j<w; ++j) field[i][j] = 0;
        for(int i=0; i<h; ++i) {
            for(int j=0; j<w; ++j) {
                cin >> field[i][j];
            }
        }

        int ans = 0;
        for(int i=0; i<h; ++i) {
            for(int j=0; j<w; ++j) {
                if(field[i][j]==1) {
                    ans++;
                    dfs(i, j);
                }
            }
        }

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

C++: 
#include <vector>
#include <list>
#include <map>
#include <set>
#include <queue>
#include <stack>
#include <algorithm>
#include <sstream>
#include <iostream>
#include <string>

using namespace std;

int H, W, m[55][55], dx[] = {1,1,0,-1,-1,-1,0,1}, dy[] = {0,1,1,1,0,-1,-1,-1};
bool flag[55][55];

void dfs(int y, int x) {
	for (int k = 0; k < 8; k++) {
		int nx = x + dx[k] , ny = y + dy[k];
		if (0<=ny && ny<H && 0<=nx && nx<W) {
			if (flag[ny][nx] && m[ny][nx]==1) {
				flag[ny][nx] = false;
				dfs(ny, nx);
			}
		}
	}
}

int main() {
	
	while (1) {

		cin >> W >> H;
		if (W==0 && H==0) break;
	
		for (int i = 0; i < H; i++) {
			for (int j = 0; j < W; j++) {
				cin >> m[i][j];
				flag[i][j] = true;
			}
		}

		int cnt = 0;
		for (int i = 0; i < H; i++) {
			for (int j = 0; j < W; j++) {
				if (m[i][j] == 1 && flag[i][j]) cnt++;
				flag[i][j] = false;
				if(m[i][j]==1) dfs(i, j);
			}
		}

		cout << cnt<<endl;

	}
	return 0;
}

C++: #include <stdio.h>
int i,j,RB[51][51],N,M,ans,a[8][2]={-1,0,1,0,0,-1,0,1,-1,-1,-1,1,1,-1,1,1};void bfs(int x, int y) {RB[x][y]=0;for (int q=0,nx,ny;q<8;q++) {nx=x+a[q][0],ny=y+a[q][1];if (nx>=0 && nx<N && ny>=0 && ny<M && RB[nx][ny]) bfs(nx,ny);}}
int main() {while (1) {scanf("%d %d",&M,&N);if (!N && !M) return 0;ans=0;for (i=0;i<N;i++) for (j=0;j<M;scanf("%d",&RB[i][j++]));for (i=0;i<N;i++) for (j=0;j<M;j++) if (RB[i][j]) bfs(i,j),ans++;printf("%d\n",ans);}}