Go: package main

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

const (
	initialBufSize = 100000
	maxBufSize     = 1000000
)

var sc *bufio.Scanner

func initScanner(r io.Reader) *bufio.Scanner {
	buf := make([]byte, initialBufSize)

	sc := bufio.NewScanner(r)
	sc.Buffer(buf, maxBufSize)
	sc.Split(bufio.ScanWords) // bufio.ScanLines
	return sc
}

func main() {
	sc = initScanner(os.Stdin)
	resolve()
}

func resolve() {
	results := []int{}
	for true {
		w, h := scanInt(sc), scanInt(sc)
		if w == 0 && h == 0 {
			break
		}
		grid := make([][]int, h)
		for i := 0; i < h; i++ {
			grid[i] = make([]int, w)
			for j := 0; j < w; j++ {
				grid[i][j] = scanInt(sc)
			}
		}
		num := 0
		for i := range loop0(h) {
			for j := range loop0(w) {
				start := pos{y: i, x: j}
				if grid[start.y][start.x] == 0 {
					continue
				}
				num++
				_dfs(grid, w, h, start)
			}
		}
		results = append(results, num)
	}
	for _, v := range results {
		fmt.Println(v)
	}
	return
}

func _dfs(grid [][]int, w, h int, start pos) {
	grid[start.y][start.x] = 0
	for _, df := range []pos{
		pos{1, 0}, pos{-1, 0},
		pos{0, -1}, pos{0, 1},
		pos{1, 1}, pos{-1, -1},
		pos{-1, 1}, pos{1, -1},
	} {
		np := addPos(start, df)
		if np.y < 0 || h <= np.y || np.x < 0 || w <= np.x {
			continue
		}
		if grid[np.y][np.x] == 0 {
			continue
		}
		_dfs(grid, w, h, np)
	}
}

type pos struct{ x, y int }

func addPos(p, d pos) pos {
	return pos{
		x: p.x + d.x,
		y: p.y + d.y,
	}
}

func loop0(n int) chan int {
	return loop(0, n-1, 1)
}

func loop1(n int) chan int {
	return loop(1, n, 1)
}

func loop(s, e, d int) chan int {
	ch := make(chan int)
	go func() {
		for i := s; i <= e; i += d {
			ch <- i
		}
		close(ch)
	}()
	return ch
}

// snip-scan-funcs
func scanInt(sc *bufio.Scanner) int {
	sc.Scan()
	i, _ := strconv.Atoi(sc.Text())
	return int(i)
}
func scanString(sc *bufio.Scanner) string {
	sc.Scan()
	return sc.Text()
}

C++: #include <iostream>
#include <vector>
using namespace std;
int d[3] = {0,1,-1};
void dfs(int x,int y,vector<vector<int> > &field){
  if((x < 0 || y < 0 || x >= field[0].size() || y >= field.size()) || field[y][x] == 0)return ;
  field[y][x] = 0;
  for(int i = -1;i <= 1;i++){
	for(int j = -1;j <= 1;j++){
	  if(i == 0 && j == 0)continue;
	  dfs(x+i,y+j,field);
	}
  }
  
}

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

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

struct Graph{
	vector<vector<int>> fld;
	
	Graph(int h,int w) : fld( h,vector<int>(w) ){}
	
	void dfs(int x, int y){
		
		fld.at(x).at(y) = 2;
		for(int i=-1; i<=1; i++){
			for(int j=-1; j<=1; j++){
				int h = fld.size();
				int w = fld.at(0).size();
				if(x+i<0||h-1<x+i||y+j<0||w-1<y+j) continue;
				if(fld.at(x+i).at(y+j)!=1) continue;
				dfs(x+i,y+j);
			}
		}
		return;
	}
	
};

int main() {
	while(1){
		int w,h;
		cin >> w >> h;
		if(w==0&&h==0) break;
		
		Graph graph(h,w);
		for(int i=0; i<h; i++){
			for(int j=0; j<w; j++){
				int s;
				cin >> s;
				graph.fld.at(i).at(j) =  s;
			}
		}
		
		int cnt{};
		for(int i=0; i<h; i++){
			for(int j=0; j<w; j++){
				if(graph.fld.at(i).at(j)==1) {
					graph.dfs(i,j);
					cnt++;
				}
				
			}
			
		}
		cout << cnt << endl;
	}
	
}

C++: /*
AizuOnline A1160
How many islands
13/03/13 RUNTIME Error
*/
#include <stdio.h>
#include <stdlib.h>

int width = 10;
int height = 10;

char kajuen[100][101];

char search_next(int * x,int * y)
{
  int i,j;
/* printf("SEARCH =%d %d\n",*x,*y); */
  i = *x;j = *y;
  goto START;
  for(i=0;i<height;i++)
    for(j=0;j<width;j++)
      {
      START:
	//	printf("SEARCH =%d %d:",i,j);
	if(kajuen[i][j]=='1')
	  { *x=i;*y=j;
	    return(kajuen[i][j]);
	  }
      }
  return(0);
}

void paint(int p,char f,int x,int y)
{
  int i,j;

#ifdef DEBUG2
  printf("P=%d %d %c %c",x,y,p,f);
  printf("F=%c N=%c %c %c\n",kajuen[x+1][y],kajuen[x][y+1],owner[x+1][y],owner[x][y+1]);
#endif
  //owner[x][y]=p+'A';
  kajuen[x][y]='0';
  for(i=x-1;i<=x+1;i++)
    for(j=y-1;j<=y+1;j++)
      if((i >=0) && (i <height) && (j >= 0) && (j <width) && !(x==i&&y==j))
	{
	  //printf("p:%d %d %d %d",x,y,i,j);
	if(kajuen[i][j] == f)
	  paint(p,f,i,j);
	}
}

int devide_kajuen()
{
  int x,y;
  char person;
  char f;

  
  x=0;y=0;
  person = 0;
  while(f=search_next(&x,&y) != 0)
    {   
      f = kajuen[x][y];
      paint(person,f,x,y);
      person ++;

    }
  return(person);
}
void clear_table()
{
  int i,j;
  for(i=0;i<100;i++)
      for(j=0;j<101;j++)
      {
        kajuen[i][j]='\0';
      }   
}
main()
{
  int n;
  int i,j;


  while(EOF != scanf("%d %d",&width,&height) && (width || height))
    {
      clear_table();
      for(i=0;i<height;i++)
	for(j=0;j<width;j++)
	  {  scanf(" %c",&(kajuen[i][j])); 
	  }      

      n = devide_kajuen();
      printf("%d\n",n);      
    }

  return(0);
}