Go: package main

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

func getScanner(fp *os.File) *bufio.Scanner {
	scanner := bufio.NewScanner(fp)
	scanner.Split(bufio.ScanWords)
	scanner.Buffer(make([]byte, 1000005), 1000005)
	return scanner
}

func getNextString(scanner *bufio.Scanner) string {
	scanner.Scan()
	return scanner.Text()
}

func getNextInt(scanner *bufio.Scanner) int {
	i, _ := strconv.Atoi(getNextString(scanner))
	return i
}

func getNextInt64(scanner *bufio.Scanner) int64 {
	i, _ := strconv.ParseInt(getNextString(scanner), 10, 64)
	return i
}

func getNextUint64(scanner *bufio.Scanner) uint64 {
	i, _ := strconv.ParseUint(getNextString(scanner), 10, 64)
	return i
}

func getNextFloat64(scanner *bufio.Scanner) float64 {
	i, _ := strconv.ParseFloat(getNextString(scanner), 64)
	return i
}

func main() {
	fp := os.Stdin
	wfp := os.Stdout
	cnt := 0

	if os.Getenv("MASPY") == "ますピ" {
		fp, _ = os.Open(os.Getenv("BEET_THE_HARMONY_OF_PERFECT"))
		cnt = 0
	}
	if os.Getenv("MASPYPY") == "ますピッピ" {
		wfp, _ = os.Create(os.Getenv("NGTKANA_IS_GENIUS10"))
	}

	scanner := getScanner(fp)
	writer := bufio.NewWriter(wfp)
	for solve(scanner, writer) {

	}
	for i := 0; i < cnt; i++ {
		fmt.Fprintln(writer, "-----------------------------------")
		solve(scanner, writer)
	}
	writer.Flush()
}

func solve(scanner *bufio.Scanner, writer *bufio.Writer) bool {
	sol := solver{}
	sol.w = getNextInt(scanner)
	sol.h = getNextInt(scanner)
	if sol.w == 0 && sol.h == 0 {
		return false
	}
	sol.land = makeInts(sol.h, sol.w)
	for y := 0; y < sol.h; y++ {
		for x := 0; x < sol.w; x++ {
			sol.land[y][x] = getNextInt(scanner)
		}
	}
	ans := 0
	for y := 0; y < sol.h; y++ {
		for x := 0; x < sol.w; x++ {
			if sol.land[y][x] == 0 {
				continue
			}
			ans++
			sol.dfs(y, x)
		}
	}
	fmt.Fprintln(writer, ans)
	return true
}

type solver struct {
	w, h int
	land [][]int
}

func (sol *solver) dfs(y, x int) {
	if y < 0 {
		return
	}
	if y >= sol.h {
		return
	}
	if x < 0 {
		return
	}
	if x >= sol.w {
		return
	}
	if sol.land[y][x] == 0 {
		return
	}
	sol.land[y][x] = 0
	dy := [8]int{-1, -1, -1, 0, 0, 1, 1, 1}
	dx := [8]int{-1, 0, 1, -1, 1, -1, 0, 1}
	for i := 0; i < 8; i++ {
		sol.dfs(y+dy[i], x+dx[i])
	}
}
func makeInts(h, w int) [][]int {
	index := make([][]int, h, h)
	data := make([]int, h*w, h*w)
	for i := 0; i < h; i++ {
		index[i] = data[i*w : (i+1)*w]
	}
	return index
}

C++: #include <iostream>
#include <vector>
#include <utility>
using namespace std;

struct UnionFind {
    vector<int> data;
    int sz;
    UnionFind(int sz) : data(sz, -1), sz(sz){ }
    bool unionSet(int x, int y) {
        if ((x = root(x)) == (y = root(y))) return false;
        if (data[x] > data[y]) swap(x, y);
        data[x] += data[y]; data[y] = x; sz--;
        return true;
    }
    bool findSet(int x, int y) { return root(x) == root(y); }
    int root(int x) { return data[x] < 0 ? x : data[x] = root(data[x]); }
    int size(int x) { return -data[root(x)]; }
    int size() { return sz; }
};

int main() {
  int w, h;
  while (cin >> w >> h) {
    if (w == 0 && h == 0) {
      break;
    }
    int count = 0;
    vector<vector<int>> c(h, vector<int>(w));
    for (int i = 0; i < h; i++) {
      for (int j = 0; j < w; j++) {
        cin >> c[i][j];
        if (c[i][j] == 0) {
          count++;
        }
      }
    }
    auto idx = [&](int i, int j) {
      return i*w + j;
    };
    auto outfield = [&](int i, int j) {
      return i < 0 || i >= h || j < 0 || j >= w;
    };
    UnionFind uf(w*h);
    for (int i = 0; i < h; i++) {
      for (int j = 0; j < w; j++) {
        for (int x = -1; x <= 1; x++) {
          for (int y = -1; y <= 1; y++) {
            if (outfield(i + x, j + y)) {
              continue;
            }
            if (c[i][j] == 1 && c[i + x][j + y] == 1) {
              uf.unionSet(idx(i, j), idx(i + x, j + y));
            }
          }
        }
      }
    }
    cout << uf.size() - count << endl;
  }
}

C++: #include <iostream>

using namespace std;

bool isVisited[50][50] = { false };
int isLand[50][50] = { 0 };

void dfs(int x, int y, int w, int h)
{
  if (x < 0 || x >= w || y < 0 || y >= h) return;
  if (isVisited[x][y] == true) return;
  if (isLand[x][y] == 0) return;

  isVisited[x][y] = true;

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

  for (int i = 0; i < 8; i++) {
    dfs(x + dx[i], y + dy[i], w, h);
  }
}

int main()
{
  int w, h;
  while (1) {
    cin >> w >> h;
    if (w == 0 && h == 0) break;
    
    for (int i = 0; i < h; i++) {
      for (int j = 0; j < w; j++) {
        cin >> isLand[j][i];
        isVisited[j][i] = false;
      }
    }

    int count = 0;
    for (int i = 0; i < h; i++) {
      for (int j = 0; j < w; j++) {
        if (isVisited[j][i] == false && isLand[j][i] == 1) {
          dfs(j, i, w, h);
          count++;
        }
      }
    }
    cout << count << endl;
  }
}

C++: #include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define rep(i, n) for(ll i = 0; i < n; i++)
#define FOR(i, m, n) for(ll i = m; i < n; i++)
#define all(vec) vec.begin(), vec.end()
#define tmax(x, y, z) max((x), max((y), (z)))
#define tmin(x, y, z) min((x), min((y), (z)))
ll MM = 1000000000; ll mod = MM + 7; ll MMM=9223372036854775807;//2^63 -1
ll GCD(ll x, ll y){ if(y == 0) return x; else return GCD(y, x % y);}
ll LCM(ll x, ll y){ return x / GCD(x, y) * y;}
template<class T> inline bool chmin(T& a, T b){ if(a > b){ a = b; return true;} return false;}
template<class T> inline bool chmax(T& a, T b){ if(a < b){ a = b; return true;} return false;}
const ll INF = 1LL << 60;
using Graph = vector<vector<ll>>;
int dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1};
int ddx[8] = {1, 1, 0, -1, -1, -1, 0, 1}, ddy[8] = {0, 1, 1, 1, 0, -1, -1, -1};
//cout << fixed << setprecision(10);

int field[100][100];
ll w, h;


void dfs(ll y, ll x){
    field[y][x] = 0;
    rep(i, 8){
        ll ny = y + ddy[i], nx = x + ddx[i];
        if(0 <= ny && ny < h && 0 <= nx && nx < w && field[ny][nx]){
            dfs(ny, nx);
        }
    }
}


int main(){
    while(1){
        cin >> w >> h;
        if(!w && !h) break;
        rep(hi, h){
            rep(wi, w){
                cin >> field[hi][wi];
            }
        }

        ll ans = 0;
        rep(hi, h){
            rep(wi, w){
                if(field[hi][wi]){
                    dfs(hi, wi);
                    ans++;
                }
            }
        }

        cout << ans << endl;
    }
}