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 <cstdio>
#include <algorithm>
#include <string>
#include <vector>
#include <map>
#include <set>
using namespace std;

struct UnionFind {
        int n;
        vector<int> parent;
        vector<int> rank;
        vector<int> num;
        int find(int x) {
                if (parent[x] == x) return  x;
                return parent[x] = find(parent[x]);
        }
        UnionFind(int n_) {
                n = n_;
                parent.resize(n);
                for (int i = 0; i < n; i ++) parent[i] = i;
                rank.assign(n, 0);
                num.assign(n, 1);
        }
        void unite(int x, int y) {
                if ((x = find(x)) != (y = find(y))) {
                        if (rank[x] < rank[y]) {
                                parent[x] = y;
                                num[y] += num[x];
                        } else {
                                parent[y] = x;
                                if (rank[x] == rank[y]) rank[x] ++;
                                num[x] += num[y];
                        }
                        n --;
                }
        }
        bool same(int x, int y) { return find(x) == find(y); }
        int get() { return n; }
        int get(int x) { return num[find(x)]; }
};

int main() {
        int w, h;
        while (scanf("%d%d", &w, &h), w) {
                vector<vector<int>> s(h, vector<int> (w));
                int lands = 0;
                map<pair<int, int>, int> ptol;
                for (int i = 0; i < h; i ++) {
                        for (int j = 0; j < w; j ++){
                                scanf("%d", &s[i][j]);
                                if (s[i][j]) {
                                        ptol[make_pair(i, j)] = lands;
                                        lands ++;
                                }
                        }
                }
                UnionFind uf(lands);
                auto get = [&](int a, int b) { return ptol[make_pair(a, b)]; };
                for (int i = 0; i < h; i ++) {
                        for (int j = 0; j < w; j ++) {
                                if (s[i][j]) {
                                        if (i - 1 >= 0 && j + 1 < w && s[i - 1][j + 1]) uf.unite(get(i, j), get(i - 1, j + 1));
                                        if (j + 1 < w && s[i][j + 1])                   uf.unite(get(i, j), get(i, j + 1));
                                        if (i + 1 < h && j + 1 < w && s[i + 1][j + 1])  uf.unite(get(i, j), get(i + 1, j + 1));
                                        if (i + 1 < h && s[i + 1][j])                   uf.unite(get(i, j), get(i + 1, j));
                                }
                        }
                }
                printf("%d\n", uf.get());
        }
        return 0;
}

C++: #include <iostream>
#define UMI 0
#define RIKU 1
using namespace std;

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

void pr(){
  for( int i=0;i<h;i++ ){
    for( int j=0;j<w;j++ )
      cout << c[i][j] << " ";
    cout << endl;
  }
}

void check( int x,int y){
  if( x<0 || x>=h ) return;
  if( y<0 || y>=w ) return;
  if( c[x][y]==UMI ) return;

  c[x][y] = UMI;
  check( x-1, y-1);
  check( x-1, y  );
  check( x-1, y+1);
  check( x  , y-1);
  check( x  , y+1);
  check( x+1, y-1);
  check( x+1, y  );
  check( x+1, y+1);
}

int main(){
  while( cin>>w>>h,w&&h ){
    for( int i=0;i<h;i++ )
      for( int j=0;j<w;j++ )
	cin >> c[i][j];
    //cout << w <<" "<< h<<endl;
    //    pr();
    int sum = 0;
    for( int i=0;i<h;i++ )
      for( int j=0;j<w;j++ )
	if( c[i][j]==RIKU ){
	  ++sum;
	  check(i,j);
	}
    cout << sum << endl;
  }

  return 0;
}

C++: #include <cstdio>
#include <cstring>

char map[51][51];
int res;
int w,h;

int dfs(int sx, int sy) {
    if(sx<0 || sx>w-1 || sy<0 || sy>h-1) return 0;
    if(map[sy][sx] == '0') return 0;

    map[sy][sx] = '0';

    dfs(sx+1,sy);
    dfs(sx,sy+1);
    dfs(sx-1,sy);
    dfs(sx,sy-1);
    dfs(sx+1,sy+1);
    dfs(sx+1,sy-1);
    dfs(sx-1,sy+1);
    dfs(sx-1,sy-1);
    return 1;
}

int main(void)
{
    int px,py;

    while(true)
    {
        res = 0;
        scanf("%d%d", &w, &h);
        if(!w && !h) break;
        for(int j=0; j < h; j++)
        for(int i=0; i < w; i++)
            scanf("%s", &map[j][i]);

        for(int j=0; j < h; j++)
        for(int i=0; i < w; i++)
            res += dfs(i, j);

        printf("%d\n", res);
    }

    return 0;
}