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 <algorithm>
#include <bitset>
#include <cmath>
#include <ctime>
#include <iostream>
#include <list>
#include <map>
#include <math.h>
#include <numeric>
#include <queue>
#include <set>
#include <stack>
#include <stdio.h>
#include <string>
#include <tuple>
#include <vector>
 
using namespace std;
using Graph = vector<vector<int>>;

#define rep(i,n) for(int i = 0; i < (n); i++)
#define all(a) begin(a),end(a)
 
typedef long long ll;
typedef pair<int,int> P;
const int inf=1000000007;
const ll mod=1000000007;
const double PI=3.14159265358979323846;
 
int dx[] = {1,-1,0,0};
int dy[] = {0,0,1,-1};
 
ll gcd(ll a, ll b){
  if (b==0) return a;
  else return gcd(b,a%b);
}
 
int cans(bool f){
  if(f) cout << "Yes" << endl;
  else cout << "No" << endl;
  return 0;
}





int W,H;
vector<vector<int>> field;



void dfs(int y,int x){
  field[y][x] = 0;
  for(int i = -1; i <= 1; i++){
    for(int j = -1; j <= 1; j++){
      
      int nx,ny; 
      nx = x + i;
      ny = y + j;
      if (ny < 0 || ny >= H || nx < 0 || nx >= W || field[ny][nx] == 0) continue;
      dfs(ny,nx);
    }
  }
}

int main(){
  while(cin >> W >> H){
    if(W == 0 || H == 0) break;
    field.assign(H,vector<int>(W,0));
    rep(i,H){
      rep(j,W) cin >> field[i][j];
    }
    
    int ans = 0;
    rep(i,H){
      rep(j,W){
	if(field[i][j] == 0) continue;
	ans++;
	dfs(i,j);
      }
    }
    cout << ans << endl;
  }
}












// void dfs(int h, int w) {
//     field[h][w] = 0;

//     // 八方向を探索
//     for (int dh = -1; dh <= 1; ++dh) {
//         for (int dw = -1; dw <= 1; ++dw) {
//             int nh = h + dh, nw = w + dw;

//             // 場外アウトしたり、0 だったりはスルー
//             if (nh < 0 || nh >= H || nw < 0 || nw >= W) continue;
//             if (field[nh][nw] == 0) continue;

//             // 再帰的に探索
//             dfs(nh, nw);
//         }
//     }
// }

// int main() {
//     // 入力受け取り
//     while (cin >> W >> H) {
//         if (H == 0 || W == 0) break;
//         field.assign(H, vector<int>(W, 0));
//         for (int h = 0; h < H; ++h) for (int w = 0; w < W; ++w) cin >> field[h][w];

//         // 探索開始
//         int count = 0;
//         for (int h = 0; h < H; ++h) {
//             for (int w = 0; w < W; ++w) {
//                 if (field[h][w] == 0) continue; // 残島じゃなかったらスルー
//                 dfs(h, w);
//                 ++count;
//             }
//         }
//         cout << count << endl;
//     }
// }

C++: #include<bits/stdc++.h>
using namespace std;
int w,h,c[50][50],ans;
vector<int> out;
bool dfs(int x,int y);
int main(){
  while(1){
    ans = 0;
    for(int i=0;i<50;i++){
      for(int l=0;l<50;l++){
        c[i][l] = 0;
      }
    }
    cin >> w >> h;
    if(w == 0 && h == 0){
      break;
    }
    for(int i=0;i<h;i++){
      for(int l=0;l<w;l++){
         cin >> c[l][i];
      }
    }
    for(int i=0;i<h;i++){
      for(int l=0;l<w;l++){
        if(c[l][i] == 1){
          dfs(l,i);
          ans++;
        }
      }
    }
    out.push_back(ans);
  }
  for(int i=0;i<out.size();i++){
    cout << out[i] << endl;
  }
}
bool dfs(int x,int y){
  if(x<0 || x>=w || y<0 || y>=h || c[x][y] == 0) return false;
  c[x][y] = 0;
  for(int dx=-1;dx<=1;dx++){
    for(int dy=-1;dy<=1;dy++){
      if(dfs(x+dx,y+dy)){
        return true;
      }
    }
  }
  return false;
}

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

int w, h;
int c[50][50], flag[50][50];

int f(int x, int y){
    if(x >= w || x < 0 || y >= h || y < 0) return 0;
    if(flag[x][y] == 1 || c[x][y] == 0) return 0;
    flag[x][y] = 1;
    f(x+1,y);
    f(x-1,y);
    f(x,y+1);
    f(x,y-1);
    f(x+1,y+1);
    f(x+1,y-1);
    f(x-1,y+1);
    f(x-1,y-1);
    return 1;
}

int main(){
    do{
        int sum = 0;
        cin >> w >> h;
        if(w == 0 && h == 0) return 0;
        for(int y = 0; y < h; y++){
            for(int x = 0; x < w; x++){
                cin >> c[x][y];
                flag[x][y] = 0;
            }
        }
        for(int y = 0; y < h; y++){
            for(int x = 0; x < w; x++){
                sum += f(x,y);
            }
        }
        cout << sum << endl;
    }while(true);

    return 0;
}

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 < w; i++){
            for (int j = 0; j < h; j++){
                if (c[i][j] == 1){
                    dfs(w, h, i, j);
                    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;
int ans;
int map[100][100];
void dfs(int x,int y,int w,int h);
int dx[8] = {1,1,0,-1,-1,-1,0,1},dy[8] = {0,1,1,1,0,-1,-1,-1};

int main(){
  int w,h;
  while(cin>>w>>h){
    ans=0;
    if(w == 0 && h == 0)break;
    for(int i = 0;i<h;i++)
      for(int j = 0;j<w;j++) 
	cin>>map[i][j];
    for(int i = 0;i<h;i++)
      for(int j = 0;j<w;j++){
	if(map[i][j] == 1){
	  map[i][j] = 0;
	  ans++;
	  dfs(i,j,w,h);
	}
      }
    // cout<<"map"<<endl;
    // for(int a=0;a<h;a++){
    //   for(int b=0;b<w;b++) cout<<map[a][b];
    //   cout<<endl;
    // }
    // cout<<endl;
    cout<<ans<<endl;
  }
  return 0;
}

void dfs(int x,int y,int w,int h){
  //cout<<"LK+LKJ"<<endl;
  int nx,ny;
  for(int i = 0;i<8;i++){
    nx = x+dx[i]; ny = y+dy[i];
    if(nx>=0 && nx<w && ny>=0 && ny<h && map[ny][nx] == 1){
      map[ny][nx] = 0;
      dfs(nx,ny,w,h);
    }
  }
}

C++: #include<iostream>
#include<stack>
#include<string.h>
using namespace std;

int landscape[52][52];
int dx[8] = {1, 0, -1, 0, 1, 1, -1, -1};
int dy[8] = {0, 1, 0, -1, 1, -1, 1, -1};

int main() {
  int w,h,t;
  while(cin>>w>>h, w||h) {
    memset(landscape, 0, sizeof(landscape));
    for(int i=1; i<=h; ++i)
      for(int j=1; j<=w; ++j)
	cin>>landscape[i][j];

    int count = 0;
    for(int i=1; i<=h; ++i) {
      for(int j=1; j<=w; ++j) {
	if(landscape[i][j] == 1) {
	  count++;
	  stack< pair<int, int> > st;
	  st.push(pair<int,int>(i,j));
	  while(!st.empty()) {
	    pair<int,int> p = st.top();
	    st.pop();
	    landscape[p.first][p.second] = 0;
	    for(int k=0; k<8; ++k)
	      if(landscape[p.first+dx[k]][p.second+dy[k]])
		st.push(pair<int,int>(p.first+dx[k], p.second+dy[k]));
	  }
	}
      }
    }

    cout<<count<<endl;
  }
}