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>
#include <cmath>
#include <vector>

using namespace std;

#define loop(i,a,b) for(int i=(a);i<int(b);i++)
#define rep(i,b) loop(i,0,b)

int c[200][200];
int vis[200][200];
int w,h;


void dfs(int ci, int cj){
    vis[ci][cj] = true;
    int di[] = {0,1,0,-1, 1,1,-1,-1};
    int dj[] = {1,0,-1,0, -1,1,-1,1};
    rep(d,8){
        int ni = ci+di[d];
        int nj = cj+dj[d];
        if(ni < 0 || nj < 0) continue;
        if(ni >= h || nj >= w) continue;
        if(vis[ni][nj]) continue;
        if(c[ni][nj]==0) continue;
        dfs(ni,nj);
    }
}

int main(){
    while(cin >> w >> h && w){
        rep(i,h)rep(j,w) cin >> c[i][j], vis[i][j] = 0;
        int ans = 0;
        rep(i,h)rep(j,w){
            if(vis[i][j]) continue;
            if(c[i][j] == 0) continue;
            dfs(i,j);
            ans++;
        }
        cout << ans << endl;
    }
}

C++: #include <iostream>
#include <algorithm>

using namespace std;

int c[50][50];

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

int ret;

int w,h;

void dfs(int x,int y){
	if(c[x][y] == 0) return;
	c[x][y] = 0;
	for(int i=0;i<8;i++){
		if(x+dx[i] < 0 || x+dx[i] >= w) continue;
		if(y+dy[i] < 0 || y+dy[i] >= h) continue;
		dfs(x+dx[i],y+dy[i]);
	}
}

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

C++: #include<iostream>
#include<algorithm>
#include<vector>
using namespace std;
int w,h;
char field[55][55];
int dx[]={1,-1,0,0,-1,-1,1,1};
int dy[]={0,0,1,-1,1,-1,1,-1};

int used[55][55];
void dfs(int y,int x){
  if(used[y][x]==1)return ;
  used[y][x]=1;
  for(int i=0;i<8;i++){
    int ny=y+dy[i];
    int nx=x+dx[i];
    if(0<=ny&&ny<h&&0<=nx&&nx<w&&field[ny][nx]=='1'){
      dfs(ny,nx);
    }
  }
  return ;
}
int main(){
  while(1){
    cin >>w>>h;
    if(w==0&&h==0) break;
    for(int i=0;i<55;i++){
      for(int j=0;j<55;j++){
        used[i][j]=0;
      }
    }
    for(int i=0;i<h;i++){
      for(int j=0;j<w;j++){
        cin >>field[i][j];
      }
    }
    int cnt=0;
    for(int i=0;i<h;i++){
      for(int j=0;j<w;j++){
        if(used[i][j]==1)continue;
        if(field[i][j]=='1'){
          cnt++;
          dfs(i,j);
        }
      }
    }
    cout << cnt << endl;
  }
}

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

#define MAX 51

bool field[MAX][MAX];
int cnt;
int H, W;

void dfs(int x, int y){
  field[y][x] = 0;
  
  for(int dx = -1 ; dx <= 1 ; dx++){
    for(int dy = -1 ; dy <= 1 ; dy++){
      int nx = x + dx;
      int ny = y + dy;
      if(0 <= nx && nx < W && 0 <= ny && ny < H && field[ny][nx] == 1) dfs(nx, ny);
    }
  }
}

int main(){
  while(cin >> W >> H){
    cnt = 0;
    if(W == 0 && H == 0) break;
    for(int i = 0 ; i < H ; i++){
      for(int j = 0 ; j < W ; j++){
	cin >> field[i][j];
      }
    }

    for(int i = 0 ; i < H ; i++){
      for(int j = 0 ; j < W ; j++){
	if(field[i][j] == 1){
	  dfs(i, j);
	  cnt++;
	}
      }
    }
    cout << cnt << endl;
  }
  return 0;
}

C++: /* {{{ Shinobu kawaii */
/*
  ______   __        _                  __                 
.' ____ \ [  |      (_)                [  |                
| (___ \_| | |--.   __   _ .--.   .--.  | |.--.   __   _   
 _.____`.  | .-. | [  | [ `.-. |/ .'`\ \| '/'`\ \[  | | |  
| \____) | | | | |  | |  | | | || \__. ||  \__/ | | \_/ |, 
 \______.'[___]|__][___][___||__]'.__.'[__;.__.'  '.__.'_/ 
                                                           
*/
/* }}} */

// #define int long long

/* cpp template {{{ */
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <climits>
#include <iostream>
#include <vector>
#include <string>
#include <sstream>
#include <algorithm>
#include <utility>
#include <set>
#include <map>
#include <stack>
#include <queue>
#include <deque>
#include <functional>
using namespace std;

/* short */
#define pb push_back
#define mp make_pair
#define print(x) cout << x << '\n'
#define Fi first
#define Se second

/* REPmacro */
#define REPS(i, a, n) for (int i = (a); i < (n); i++)
#define REP(i, n) for (int i = 0; i < (n); i++)
#define RREP(i, n) for (int i = 1; i <= (n); i++)
#define DEPS(i, a, n) for (int i = (a); i >= n; i--)
#define DEP(i, n) for (int i = (n); i >= 0; i--)

/* typedef */
typedef long long ll;
typedef unsigned long long ull;
typedef vector<int> vi;
typedef vector<vector<int> > vii;
typedef pair<int, int> pii;

/* const */
const int INF = 999999999;
const int dx[] = {0, 1, 0, -1, 1, -1, 1, -1}, dy[] = {1, 0, -1, 0, 1, -1, -1, 1};

/* func */
inline bool is_uruu(int y) {return (y % 4 == 0 && (y % 100 != 0 || y % 400 == 0));}
inline bool inside(int y, int x, int H, int W) {return (y >= 0 && x >= 0 && y < H && x < W);}

/* }}} */

bool field[56][56];
int w, h;

void dfs(int y, int x)
{
  field[y][x] = false;

  REP(i, 8){
    int nx = x + dx[i], ny = y + dy[i];
    if (!inside(ny, nx, h, w)) continue;
    if (!field[ny][nx]) continue;
    dfs(ny, nx);
  }
}

signed main()
{
  cin.tie(0);
  ios::sync_with_stdio(false);
  
  for (; cin >> w >> h, w || h; ){
    REP(i, h){
      REP(j, w){
        cin >> field[i][j];
      }
    }

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

  return (0);
}

C++: #include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair<int,int> pii;
typedef vector<int> VI;
typedef vector<VI> VVI;
const double PI = 3.14159265358979323846;
const double EPS = 1e-12;
const int INF = numeric_limits<int>::max() / 2;
const int NEG_INF = numeric_limits<int>::min() / 2;

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

void dfs(int x,int y){
    tiles[x][y]=0;

    for(int dx=-1;dx<=1;dx++){
      for(int dy=-1;dy<=1;dy++){
        int nx=x+dx,ny=y+dy;

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

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

  while(true){
    for(int i=0;i<51;i++){
      for(int j=0;j<51;j++){
        tiles[i][j]=0;
      }
    }
    int ans=0;
    cin >> w >> h;
    if(w==0) break;
    for(int i=0;i<h;i++){
      for(int j=0;j<w;j++){
        cin >> tiles[j][i];
      }
    }
    for(int i=0;i<h;i++){
      for(int j=0;j<w;j++){
        if(tiles[j][i]==1){
           dfs(j,i);
           ans++;
         }
      }
    }
    cout << ans << endl;
  }
}