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 foo(int c[2][60][60], int y, int x){
	if(c[1][y][x] == 1) return 0;
	c[1][y][x] = 1;
	if(c[0][y][x] == 0) return 0;
	
	for(int i = -1; i <= 1; i++)
		for(int j = -1; j <= 1; j++)
			foo(c, y+i, x+j);
	
	return 1;
}

int main(){
	int h, w;
	
	while(1){
		int  c[2][60][60] = {}, count = 0;
		
		cin>>w>>h;
		
		if(w == 0 && h == 0) break;
		
		for(int i = 1; i <= h; i++)
			for(int j = 1; j <= w; j++)
				cin>>c[0][i][j];
		
		for(int i = 1; i <= h; i++)
			for(int j = 1; j <= w; j++)
				if(foo(c, i, j) == 1) count++;
				
		cout<<count<<endl;
	}
	return 0;
}

C++: #include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;

int field[52][52];

void dfs(int y, int x)
{
  static const int dy[] = {-1, -1, -1, 0, 0, 1, 1, 1};
  static const int dx[] = {-1, 0, 1, -1, 1, -1, 0, 1};

  if (field[y][x] != 1)
    return;
  field[y][x] = 2;
  for (int i = 0; i < 8; ++i) {
    dfs(y+dy[i], x+dx[i]);
  }
}

int main()
{
  int w, h;
  while (scanf("%d%d", &w, &h), w|h) {
    memset(field, 0, sizeof(field));
    for (int i = 1; i <= h; ++i) {
      for (int j = 1; j <= w; ++j) {
        scanf("%d", &field[i][j]);
      }
    }
    int count = 0;
    for (int i = 1; i <= h; ++i) {
      for (int j = 1; j <= w; ++j) {
        if (field[i][j] == 1) {
          ++count;
          dfs(i, j);
        }
      }
    }
    printf("%d\n", count);
  }
}

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

using ll=long long;
#define int ll

#define FOR(i,a,b) for(int i=int(a);i<int(b);i++)
#define REP(i,b) FOR(i,0,b)

int read(){
	int i;
	scanf("%lld",&i);
	return i;
}

int land[1000][1000]={-1};
int flag[1000][1000]={-1};
int dy[]={-1,-1,-1,0,0,1,1,1};
int dx[]={-1,0,1,-1,1,-1,0,1};
int cnt=0;

void isLand(int i,int j){
	REP(k,8){
		int newx=i+dx[k];
		int newy=j+dy[k];
		if(land[newx][newy]){
			if(flag[newx][newy]!=-1){
				flag[i][j]=flag[newx][newy];
				return;
			}
		}
	}
	cnt++;
	flag[i][j] = cnt;
}

signed main(){
	int w,h;
	while( w=read(),h=read(),w||h){
		cnt=0;
		
		REP(i,1000){
			REP(j,1000){
				land[i][j]=-1;
				flag[i][j]=-1;
			}
		}
		
		FOR(i,1,w+1){
			FOR(j,1,h+1){
				land[i][j]=read();
			}
		}
		
		FOR(i,1,w+1){
			FOR(j,1,h+1){
				if(land[i][j])isLand(i,j);
			}
		}
		
		cout << cnt << endl;
	}
	
}

C++: #include<iostream>
#include<string>
#include<algorithm>
#include<set>
#include<map>
#include<stack>
#include<queue>
#include<numeric>
#include<vector>
#include<cstring>
#define foreach(t,p) for(t::iterator it=p.begin();it!=p.end();p++)
#define REP(i,n) for(int i=0;i<n;i++)
using namespace std;
#define MAX_W 50

bool island[MAX_W+3][MAX_W+3];

int solve(int x,int y)
{
	if(!island[x][y]) {return 0;}

	island[x][y]= false;
	solve(x-1,y-1);
	solve(x-1,y);
	solve(x-1,y+1);
	solve(x,y-1);
	solve(x,y+1);
	solve(x+1,y+1);
	solve(x+1,y);
	solve(x+1,y-1);
//	cout << x << " " << y << endl;
	return 1;
}


int main()
{
	int w,h;
	while(cin >> w >> h &&w && h)
	{
		REP(i,MAX_W+2)REP(j,MAX_W+2) island[i][j]=false;
		REP(i,h)REP(j,w){cin >> island[i+1][j+1];}
		int kosu = 0;
		REP(i,h)REP(j,w){kosu += solve(i+1,j+1);}
		cout << kosu << endl;
		
	}
	return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
using ll = long long;
using P = pair<ll, ll>;

void dfs(int y, int x, vector<vector<int> > &C, vector<vector<int> > &used) {
    used.at(y).at(x) = 1;
    int H = C.size();
    int W = C.at(0).size();
    for (int dy = -1; dy <= 1; ++dy) {
        for (int dx = -1; dx <= 1; ++dx) {
            int ny = y + dy;
            int nx = x + dx;
            if (ny < 0 || H <= ny) continue;
            if (nx < 0 || W <= nx) continue;
            if (used.at(ny).at(nx)) continue;
            if (C.at(ny).at(nx) == 0) continue;
            dfs(ny, nx, C, used);
        }
    }
}

int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);

    while (true) {
        int W, H;
        cin >> W >> H;
        if (W == 0 && H == 0) break;
        vector<vector<int> > C(H, vector<int>(W));
        vector<vector<int> > used(H, vector<int>(W, 0));
        for (int y = 0; y < H; ++y) {
            for (int x = 0; x < W; ++x) {
                cin >> C.at(y).at(x);
            }
        }

        int ans = 0;
        for (int y = 0; y < H; ++y) {
            for (int x = 0; x < W; ++x) {
                if (C.at(y).at(x) == 1 && used.at(y).at(x) == 0) {
                    ans++;
                    dfs(y, x, C, used);
                }
            }
        }

        cout << ans << endl;
    }

    return 0;
}