Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

var sc = bufio.NewScanner(os.Stdin)
var route [][]int

func scanInt() int {
	num, _ := strconv.Atoi(scanString())
	return num
}

func scanString() string {
	sc.Scan()
	return sc.Text()
}

func init() {
	sc.Split(bufio.ScanWords)
}

func dfs(h, w int) {
	if route[h][w] == 0 {
		return
	}

	route[h][w] = 0
	for _, x := range []int{-1, 0, 1} {
		for _, y := range []int{-1, 0, 1} {
			if route[h+x][w+y] == 0 {
				continue
			}
			dfs(h+x, w+y)
		}
	}
}

func main() {
	writer := bufio.NewWriter(os.Stdout)
	for {
		w, h := scanInt(), scanInt()
		if w == 0 && h == 0 {
			break
		}

		route = make([][]int, h+2)
		route[0] = make([]int, w+2)
		for i := 1; i <= h; i++ {
			route[i] = make([]int, w+2)
			for j := 1; j <= w; j++ {
				route[i][j] = scanInt()
			}
		}
		route[h+1] = make([]int, w+2)

		total := 0
		for i := 1; i <= h; i++ {
			for j := 1; j <= w; j++ {
				if route[i][j] == 1 {
					total++
					dfs(i, j)
				}
			}
		}
		fmt.Fprintln(writer, total)
	}
	writer.Flush()
}

C++: #include <vector>
#include <list>
#include <map>
#include <set>
#include <stack>
#include <queue>
#include <deque>
#include <algorithm>
#include <utility>
#include <functional>
#include <sstream>
#include <iostream>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <ctime>
#include <climits>
#include <cassert>
using namespace std;
inline int toInt(string s) {int v; istringstream sin(s);sin>>v;return v;}
template<class T> inline string toString(T x) {ostringstream sout;sout<<x;return sout.str();}
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<string> vs;
typedef pair<int, int> pii;
typedef long long ll;
#define ALL(a) (a).begin(),(a).end()
#define RALL(a) (a).rbegin(),(a).rend()
#define EXIST(s,e) ((s).find(e)!=(s).end())
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n) FOR(i,0,n)
#define EACH(t,i,c) for(t::iterator i=(c).begin(); i!=(c).end(); ++i)
const double EPS = 1e-10;
const double PI  = acos(-1.0);

int search(int y,int x,int w,int h,vvi &v){
	int dx[] = {-1,0,1,1,1,0,-1,-1};
	int dy[] = {-1,-1,-1,0,1,1,1,0};
	if(v[y][x] == 1){
		v[y][x] = 0;
		for(int i=0;i<8;i++){
			if(y+dy[i] >= 0 && y+dy[i] < h && x+dx[i] >= 0 && x+dx[i] < w){
				search(y+dy[i],x+dx[i],w,h,v);
			}
		}
		return 1;
	}
	return 0;
}

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

C++: #include <iostream>
#include <vector>
using namespace std;
#define MAX 50

int c[MAX][MAX];

void dfs(int w, int h, int x, int y);
int main(int argc, char const *argv[]){
    int w, h, ans;

    while (cin>>w>>h, w || h){
        ans = 0;
        for (int i = 0; i < h; i++){
            for (int j = 0; j < w; j++){
                cin>>c[i][j];
            }
        }
        for (int i = 0; i < h; i++){
            for (int j = 0; j < w; j++){
                if (c[i][j] == 1){
                    dfs(w, h, j, i);
                    ans++;
                }
            }
        }
        cout<<ans<<endl;
    }
    return 0;
}

void dfs(int w, int h, int x, int y){
    int dx[8] = {1, 1, 0, -1, -1, -1, 0, 1};
    int dy[8] = {0, 1, 1, 1, 0, -1, -1, -1};
    c[x][y] = 0;

    for (int i = 0; i < 8; i++){
        int nx = x + dx[i];
        int ny = y + dy[i];

        if (0 <= nx && nx < w && 0 <= ny && ny < h && c[nx][ny] == 1){
            dfs(w, h, nx, ny);
        }
    }
    return;
}

C++: #include <iostream>
using namespace std;
void kazoeruyo(int p,int P,int box[50][50]){
  box[p][P]=0;
    if(box[p][P+1]==1) {
      box[p][P+1]=0;
      P=P+1; 
      kazoeruyo(p,P,box);
    }
    if(box[p][P-1]==1){
      box[p][P-1]=0;
      P=P-1;
      kazoeruyo(p,P,box);
    }
    if(box[p+1][P]==1){ 
      box[p+1][P]=0;
      p=p+1;
      kazoeruyo(p,P,box);
    }
    if(box[p-1][P]==1){
      box[p-1][P]=0;
      p=p-1;
      kazoeruyo(p,P,box);
    }
    if(box[p-1][P-1]==1){
      box[p-1][P-1]=0;
      p=p-1;
      P=P-1;
      kazoeruyo(p,P,box);
    }
    if(box[p-1][P+1]==1){
      box[p-1][P+1]=0;
      p=p-1;
      P=P+1;
      kazoeruyo(p,P,box);
    }
    if(box[p+1][P+1]==1){
      box[p+1][P+1]=0;
      p=p+1;
      P=P+1;
      kazoeruyo(p,P,box);
    }
    if(box[p+1][P-1]==1){
      box[p+1][P-1]=0;
      p=p+1;
      P=P-1;
      kazoeruyo(p,P,box);
    }	
}
int main(){
  int w,h,i,I,p,P,o,t,T,y,Y;
  int box[50][50];
  while(1){
    cin>>w>>h;
    if(w==0&&h==0) break;
    for(i=0;i<h;i++){
      for(I=0;I<w;I++){
	cin>>box[i][I];
      }
    }
    o=0;
    for(i=0;i<h;i++){
      for(I=0;I<w;I++){
	if(box[i][I]==1) {
	  p=i;
	  P=I;
	  kazoeruyo(p,P,box);
	  box[p][P]=1;
	}
      }
    }
    for(i=0;i<h;i++){
      for(I=0;I<w;I++){
	if(box[i][I]==1) o++;
      }
    }
    cout<<o<<endl;
    o=0;
  }
  return 0;
}