Go: ///
// File:  1160.go
// Author: ymiyamoto
//
// Created on Sun Mar  4 20:45:57 2018
//
package main

import (
	"fmt"
)

var w, h int
var graph [][]string

func dfs(visited [][]bool, x, y int) {
	visited[x][y] = true

	for i := -1; i <= 1; i++ {
		for j := -1; j <= 1; j++ {
			dx := x + i
			dy := y + j
			if 0 <= dx && dx < h && 0 <= dy && dy < w && graph[dx][dy] == "1" && !visited[dx][dy] {
				dfs(visited, dx, dy)
			}
		}
	}
}

func main() {
	for {
		fmt.Scan(&w, &h)
		if w == 0 && h == 0 {
			break
		}

		graph = make([][]string, h)
		for i := range graph {
			graph[i] = make([]string, w)
		}

		for i := 0; i < h; i++ {
			for j := 0; j < w; j++ {
				var s string
				fmt.Scan(&s)
				graph[i][j] = s
			}
		}

		visited := make([][]bool, h)
		for i := range visited {
			visited[i] = make([]bool, w)
		}

		count := 0
		for i := range graph {
			for j := range graph[i] {
				if graph[i][j] == "1" && !visited[i][j] {
					dfs(visited, i, j)
					count++
				}
			}
		}

		fmt.Println(count)
	}
}

C++: #include<iostream>
using namespace std;
int dx[]={0,1,0,-1,1,1,-1,-1},dy[]={1,0,-1,0,1,-1,1,-1};
struct E{
	int w,h;
	int ma[50][50],color[50][50];
	bool used[50][50];
	int col;
	int init(int _w,int _h)
	{
		w=_w,h=_h;
		for(int i=0;i<h;i++)
		{
			for(int j=0;j<w;j++)
			{
				cin>>ma[i][j];
				used[i][j]=color[i][j]=0;
			}
		}
	}
	void dfs(int x,int y)
	{
		used[x][y]=1;
		color[x][y]=col;
		for(int r=0;r<8;r++)
		{
			int tx=x+dx[r],ty=y+dy[r];
			if(tx<0||ty<0||tx>=h||ty>=w||ma[tx][ty]==0||used[tx][ty])continue;
			dfs(tx,ty);
		}
	}
	void solve()
	{
		col=0;
		for(int i=0;i<h;i++)
		{
			for(int j=0;j<w;j++)
			{
				if(used[i][j]||ma[i][j]==0)continue;
				col++;
				dfs(i,j);
			}
		}
		cout<<col<<endl;
	}
};
main()
{
	int a,b;
	while(cin>>a>>b,a)
	{
		E s;s.init(a,b);s.solve();
	}
}

C++: #include <cstdio>
#include <cstring>
#include <cmath>
#include <iostream>
#include <sstream>
#include <algorithm>
#include <numeric>
#include <functional>
#include <vector>
#include <queue>
#include <string>
#include <complex>

#define REP(i,n) for (int i = 0; i < (n); i++)
#define FOR(i,s,n) for (int i = (s); i < (n); i++)
#define ALLOF(c) c.begin(), c.end()
#define RANGEOF(c,i,n) c.begin() + (i), c.begin() + (i) + (n)
#define EPS 1e-9
#define INF 1000000000
using namespace std;

typedef complex<int> POINT;
template <class T>
class vevector : public vector<vector<T>>
{
public:
	using vector<vector<T>>::operator []; 
	T& operator [](const POINT &index) { return (*this)[index.real()][index.imag()]; }
};

template <class T> T read() { T t; cin >> t; return t; }
template <class T> vector<T> read(int n) { vector<T> v; REP(i,n) { v.push_back(read<T>()); } return v; }
template <class T> vevector<T> read(int n, int m) { vevector<T> v; REP(i,n) v.push_back(read<T>(m)); return v; }
template <class T> void write(const T &t) { cout << t << endl; }
template <class T> void write(const T &t, const T &t2) { cout << t << ' ' << t2 << endl; }

template <class T> void write(const vector<T> &v)
{
	ostringstream ss; 
	for (auto x : v) ss << x << ' ';
	auto s = ss.str();
	cout << s.substr(0, s.length() - 1) << endl;
}

struct _Reader { template <class T> _Reader operator ,(T &rhs) { cin >> rhs; return *this; } };
#define READ(t,...) t __VA_ARGS__; _Reader(), __VA_ARGS__

void solve();
int main() { solve(); return 0; }


/// template end ///



void solve()
{
	while (true)
	{
		READ(int, H, W);
		if (!(W|H)) { break; }
		auto field = read<char>(W, H);
		for (auto &f : field) { f.insert(f.begin(), '0'); f.push_back('0'); }
		field.insert(field.begin(), vector<char>(H+2, '0'));
		field.push_back(vector<char>(H+2, '0'));
		W += 2; H += 2;

		int count = 0;
		REP(sx,W) REP(sy,H) if (field[sx][sy] == '1')
		{
			typedef POINT P;
			queue<P> q;
			q.push(P(sx, sy));
			while (!q.empty())
			{
				P cur = q.front(); q.pop();
				if (field[cur] == '0') { continue; }
				field[cur] = '0';
				P d[] = { P(-1,-1), P(0,-1), P(1,-1), P(-1, 0), P(1, 0), P(-1,1), P(0,1), P(1,1) };
				REP(i, 8)
				{
					P next = cur + d[i];
					if (field[next] == '1') q.push(next);
				}
			}
			count++;
		}
		write(count);
	}
}

C++: #include<iostream>
#define N 51
using namespace std;

int w, h, ans = 0, map[N][N];

void search_zahyou(int w, int h);

int main(){
	while(cin >>w >>h){
		ans = 0;
		if(w == 0 && h == 0) break;
		for(int i = 0; i < h; i++){
			for(int k = 0; k < w; k++){
				cin >>map[i][k];
			}
		}
		for(int i = 0; i < h; i++){
			for(int k = 0; k < w; k++){
				if(map[i][k] == 0){
					continue;
				}
				else{
					ans++;
					search_zahyou(i, k);
				}
			}
		}
		cout <<ans <<endl;
	}
	return 0;
}

void search_zahyou(int inh, int inw){
	char searchh[8] = {-1, -1, -1, 0, 1, 1, 1, 0}, searchw[8] = {-1, 0, 1, 1, 1, 0, -1, -1};
	if(h <= inh || w <= inw){
	} else{
		map[inh][inw] = 0;
		for(int i = 0; i < 8; i++){
			if(map[inh + searchh[i]][inw + searchw[i]] == 1){
				search_zahyou(inh + searchh[i], inw + searchw[i]);
			}
		}
	}
}

C++: #include <bits/stdc++.h>
using namespace std;
#define int long long   // <-----!!!!!!!!!!!!!!!!!!!

#define rep(i,n) for (int i=0;i<(n);i++)
#define rep2(i,a,b) for (int i=(a);i<(b);i++)
#define rrep(i,n) for (int i=(n)-1;i>=0;i--)
#define rrep2(i,a,b) for (int i=(b)-1;i>=(a);i--)
#define all(a) (a).begin(),(a).end()

typedef long long ll;
typedef pair<int, int> P;
typedef tuple<int, int, int> TUPLE;
typedef vector<int> V;
typedef vector<V> VV;
typedef vector<VV> VVV;

const int INF = 1e9;
int dx[8] = {1, 0, -1, 0, 1, 1, -1, -1};
int dy[8] = {0, 1, 0, -1, 1, -1, 1, -1};

int H, W;
int s[50][50];
int d[50][50];

bool inside(int x, int y) {
    return 0 <= x && x < H && 0 <= y && y < W;
}

int bfs(int sx = -1, int sy = -1, int gx = -1, int gy = -1) {
    queue<P> que;
    que.push(P(sx, sy));

    while (!que.empty()) {
        P p = que.front(); que.pop();
        if (p.first == gx && p.second == gy)
             break;

        rep(k, 8) {
            int nx = p.first + dx[k], ny = p.second + dy[k];

            if (inside(nx, ny) && s[nx][ny] != 0 && d[nx][ny] == INF) {
                que.push(P(nx, ny));
                d[nx][ny] = d[p.first][p.second] + 1;
            }
        }
    }
    return d[gx][gy];
}

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

    while (cin >> W >> H, W) {
        rep(i, H) {
            rep(j, W) {
                cin >> s[i][j];
                d[i][j] = INF;
            }
        }

        int ans = 0;
        rep(i, H) {
            rep(j, W) {
                if (d[i][j] == INF && s[i][j] == 1) {
                    bfs(i, j);
                    ans++;
                }
            }
        }
        cout << ans << endl;
    }
}

C++: #include<bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i=0;i<n;++i)
int m[55][55];
int qx[1000000],qy[1000000];
int s,e,x,y,ans;

void push(int bx,int by){
  e++;
  qx[e]=bx;
  qy[e]=by;
}
void pop(){
  x=qx[s];
  y=qy[s];
  s++;
}
void bfs(int bx,int by){
  s=0; e=-1;
  push(bx,by);
  m[by][bx]=0;
  while(s<=e){
    pop();
    for(int i=y-1;i<y+2;++i){
      for(int j=x-1;j<x+2;++j){
	if(m[i][j]){
	  push(j,i);
	  m[i][j]=0;
	}
      }
    }
  }
}
int main(){
  int w,h;
  while(cin>>w>>h,w){
    //init
    rep(i,55) rep(j,55) m[i][j]=0;
    ans=0;
    
    rep(i,h){
      rep(j,w){
	int a; cin>>a;
	m[i][j]=a;
      }
    }
    rep(i,h) rep(j,w)
      if(m[i][j]){
	bfs(j,i);
	ans++;
      }    
    cout<<ans<<endl;
  }
  return 0;
}