Go: // AOJ 1160: How Many Islands? http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=1160

package main

import (
	"bufio"
	"container/list"
	"fmt"
	"os"
	"strconv"
)

var SEA = 0
var LAND = 1

func nextInt(sc *bufio.Scanner) int {
	sc.Scan()
	v, _ := strconv.Atoi(sc.Text())
	return v
}

func discoverIslands(M, V [][]int, H, W int) int {
	// 島を探す
	queue := list.New()
	islands := 0
	for i := 1; i <= H; i++ {
		for j := 1; j <= W; j++ {
			// 訪問済みの土地ならスキップ
			if V[i][j] == 1 {
				continue
			}

			// 訪問中の土地が海なら訪問済みにしてスキップ
			if M[i][j] == SEA {
				V[i][j] = 1
				continue
			}

			// 未訪問の陸地が見つかったので
			// 島の数を1つ増やし、この陸地から辿れる陸地を訪問していく
			islands++
			queue.PushBack([]int{i, j})

			for queue.Len() > 0 {
				cur := queue.Remove(queue.Front()).([]int)
				h, w := cur[0], cur[1]
				if V[h][w] == 1 {
					continue
				}
				V[h][w] = 1

				// 全方向に未訪問の陸地がないか探索
				for v := -1; v <= 1; v++ {
					for l := -1; l <= 1; l++ {
						dh := h + v
						dw := w + l
						if M[dh][dw] == LAND && V[dh][dw] == 0 {
							queue.PushBack([]int{dh, dw})
						}
					}
				}
				/*
					if M[h-1][w] == LAND {
						queue.PushBack([]int{h - 1, w})
					}
					if M[h-1][w+1] == LAND {
						queue.PushBack([]int{h - 1, w + 1})
					}
					if M[h][w+1] == LAND {
						queue.PushBack([]int{h, w + 1})
					}
					if M[h+1][w+1] == LAND {
						queue.PushBack([]int{h + 1, w + 1})
					}
					if M[h+1][w] == LAND {
						queue.PushBack([]int{h + 1, w})
					}
					if M[h+1][w-1] == LAND {
						queue.PushBack([]int{h + 1, w - 1})
					}
					if M[h][w-1] == LAND {
						queue.PushBack([]int{h, w - 1})
					}
					if M[h-1][w-1] == LAND {
						queue.PushBack([]int{h - 1, w - 1})
					}
				*/
			}
		}
	}
	return islands
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	for {
		W, H := nextInt(sc), nextInt(sc)

		if W == 0 && H == 0 {
			break
		}
		// Initialize map and visted list
		M := make([][]int, H+2)
		V := make([][]int, H+2)
		for i := 0; i < H+2; i++ {
			M[i] = make([]int, W+2)
			V[i] = make([]int, W+2)
		}
		for i := 1; i <= H; i++ {
			for j := 1; j <= W; j++ {
				M[i][j] = nextInt(sc)
			}
		}

		islands := discoverIslands(M, V, H, W)

		fmt.Println(islands)
	}
}

C++: /************************************
 * ???????????¢?´¢??§??¶?????°?????°??????????????°?????? *
 ************************************/

#include <iostream>
#include <queue>
#include <map>

#define LAND '1'  //??? char???
#define SEA  '0'   //??? char???

using namespace std;

/* ?????????
int dx[] = {1,-1,0,0};
int dy[] = {0,0,1,-1};
*/

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

bool input(vector< vector<char> > &m);
void delete_island(vector< vector< char > > &m, int x, int y);
void output(vector< vector< char> > m);


int main(){
  int w, h;
    
  while(cin >> w >> h, w && h){
    vector< vector< char > > m(h+2, vector<char>(w+2));
    input(m);
    
    int island = 0;
    for(int y = 0; y < m.size(); y++){
      for(int x = 0; x < m[y].size(); x++){
	if(m[y][x] == LAND){
	  delete_island(m,x,y);
	  island++;
	}
      }
    }
    cout << island << endl;
  }
}


bool input(vector< vector<char> > &m){
  for(int y = 0; y < m.size(); y++){
    for(int x = 0; x < m[y].size(); x++){
      if(y == 0 || x == 0 ||
	 y == m.size()-1 || x == m[y].size()-1){
	m[y][x] = SEA;
      }else{
	if(!(cin >> m[y][x])) return false;
      }
    }
  }
  return true;
}


 void delete_island(vector< vector< char > > &m, int x, int y){
   queue< pair< int, int > > q;
   q.push(make_pair(x,y));

   while(!(q.empty())){
     pair<int, int> cur = q.front();
     q.pop();
     if(m[cur.second][cur.first] == LAND){
       m[cur.second][cur.first] = SEA;
       for(int i = 0; i < sizeof(dx)/sizeof(int); i++){
	 q.push(make_pair(cur.first+dx[i],cur.second+dy[i]));
       }
     }
   }
}

void output(vector< vector< char> > m){
  for(int y = 0; y < m.size()-1; y++){
    for(int x = 0; x < m[y].size()-1; x++{
      cout << m[y][x] << " ";
    }
    cout << endl;
  }
  cout << endl;
}

C++: #include<bits/stdc++.h>
using namespace std;
int main(){
  int w,h,ans;
  bool b;
  int mp[70][70];
  while(1){
    cin>>w>>h;
    if(w==0 && h==0) break;
    for(int i=0;i<70;i++){
      for(int j=0;j<70;j++){
	mp[i][j]=0;
      }
    }
    ans=2;
    for(int i=1;i<=h;i++){
      for(int j=1;j<=w;j++){
	cin>>mp[i][j];
      }
    }
    for(int i=1;i<=h;i++){
      for(int j=1;j<=w;j++){
	b=true;
	if(mp[i][j]==1){
	  mp[i][j]=ans;
	  while(b){
	    b=false;
	    for(int k=1;k<=h;k++){
	      for(int l=1;l<=w;l++){
		if(mp[k][l]==ans){
		  for(int m=k-1;m<=k+1;m++){
		    for(int n=l-1;n<=l+1;n++){
		      if(mp[m][n]==1){
			mp[m][n]=ans;
			b=true;
		      }
		    }
		  }
		}
	      }
	    }
	  }
	  ans++;
	}
      }
    }
    cout<<ans-2<<endl;
  }
  return 0;
}

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

int h,w;
int maps[50][50];
int dy[]={-1,-1,-1,0,0,0,1,1,1};
int dx[]={-1,0,1,-1,0,1,-1,0,1};

void dfs(int y,int x);

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

void dfs(int y,int x){
  maps[y][x] = 0;
  for(int i = 0; i < 9;i++){
    int sy = y + dy[i];
    int sx = x + dx[i];
    if(sy >= 0 && sy < h && sx >= 0 && sx < w && maps[sy][sx] == 1){
      dfs(sy,sx);
    }
  }
  return;
}

C++: #include <iostream>
using namespace std;
int h,w,dp[50][50],dx[]={0,0,1,1,1,-1,-1,-1},dy[]={1,-1,0,1,-1,0,1,-1},ch[50][50],ans;
void dfs(int x,int y){
    for(int i=0;i<8;i++){
        int nx=x+dx[i];
        int ny=y+dy[i];
        if(0<=nx&&nx<h&&0<=ny&&ny<w&&dp[nx][ny]==1){
            if(ch[nx][ny]==0){
                ch[nx][ny]=1;
                dfs(nx,ny);
            }
        }
    }
    return ;
}
int main(void){
    while(1){
        cin>>w>>h;
        if(w==0&&h==0)return 0;
        ans=0;
        for(int i=0;i<h;i++)for(int j=0;j<w;j++){
            ch[i][j]=0;
            cin>>dp[i][j];
        }
        for(int i=0;i<h;i++){
            for(int j=0;j<w;j++){
                if(dp[i][j]==1&&ch[i][j]==0){
                    dfs(i,j);
                    ans++;
                }
            }
        }
        cout<<ans<<endl;
    }
}

C++: #include <iostream>

using namespace std;

int w, h;
int m[50][50];
void paint(int x, int y) {
	if (x < 0 || x >= w || y < 0 || y >= h) return;
	if (m[y][x] == 0) return;
	m[y][x] = 0;
	for (int dx = -1; dx <= 1; ++dx) for (int dy = -1; dy <= 1; ++dy) {
		paint(x+dx, y+dy);
	}
}
int main() {
	while ( cin >> w >> h, w || h ) {
		for (int y = 0; y < h; ++y) {
			for (int x = 0; x < w; ++x) {
				cin >> m[y][x];
			}
		}
		int ans = 0;
		for (int y = 0; y < h; ++y) {
			for (int x = 0; x < w; ++x) {
				if (m[y][x]) {
					paint(x, y);
					++ans;
				}
			}
		}
		cout << ans << endl;
	}
}