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 <vector>
#include <map>
#include <set>
#include <stack>
#include <queue>
#include <deque>
#include <algorithm>
#include <utility>
#include <functional>
#include <sstream>
#include <iostream>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <ctime>
#include <climits>

using namespace std;

inline int toInt(string s) { int v; istringstream sin(s); sin >> v; return v;}
template<class T> inline string toString(T x) { ostringstream sout; sout << x; return sout.str();}

typedef vector<int> vi;
typedef vector<vi>  vvi;
typedef vector<string> vs;
typedef pair<int, int> pii;
typedef long long ll;

#define ALL(a) (a).begin(),(a).end()
#define RALL(a) (a).rbegin(),(a).rend()
#define EACH(t,i,c) for(t::iretator i=(c).begin(); i!=(c).end(); ++i)
#define EXIST(s,e) ((s).find(e)!=(s).end())
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n) FOR(i,0,n)

const double EPS = 1e-10;

int seamap[52][52];
static int num = 0;

void dfs(int x, int y) {
	if(seamap[x][y] == 1) {
		seamap[x][y] = 0;

		if(seamap[x-1][y-1]) {
			dfs(x-1, y-1);
		}
		if(seamap[x][y-1]) {
			dfs(x, y-1);
		}
		if(seamap[x+1][y-1]) {
			dfs(x+1, y-1);
		}
		if(seamap[x-1][y]) {
			dfs(x-1, y);
		}
		if(seamap[x+1][y]) {
			dfs(x+1, y);
		}
		if(seamap[x-1][y+1]) {
			dfs(x-1, y+1);
		}
		if(seamap[x][y+1]) {
			dfs(x, y+1);
		}
		if(seamap[x+1][y+1]) {
			dfs(x+1, y+1);
		}
	}
}


int main() {
	int w, h;

	REP(i, 52) {
		REP(j, 52) {
			seamap[i][j] = 0;
		}
	}

	while(cin >> w >> h, (w!=0 && h!=0)) {
		FOR(i, 1, h+1) {
			FOR(j, 1, w+1) {
				int p;
				cin >> p;
				seamap[i][j] = p;
			}
		}

		FOR(i, 1, h+1) {
			seamap[i][w+1] = 0;
		}

		FOR(j, 1, w+1) {
			seamap[h+1][j] = 0;
		}
	
		num = 0;

		FOR(i, 1, 50) {
			FOR(j, 1, 50) {
				if(seamap[i][j]) {
					num++;
					dfs(i, j);
				}
			}
		}

		cout << num << endl;
	}
}

C++: #include<iostream>
#include<cstdio>
#include<cmath>
#include<cstring>
#include<string>
#include<algorithm>
#include <functional>

using namespace std;

int INF = 10000000;

bool f[50][50];
bool cell[50][50];
int w,h;

int dfs(int i,int j)
{
	if(i < 0 || j < 0 || i >= h || j >= w || f[i][j])return 0;

	if(!cell[i][j])return 0;

	f[i][j] = true;

	dfs(i-1,j);
	dfs(i+1,j);
	dfs(i,j+1);
	dfs(i,j-1);
	
	dfs(i-1,j-1);
	dfs(i-1,j+1);
	dfs(i+1,j-1);
	dfs(i+1,j+1);

	return 1;
}

int cast()
{
	int sum = 0;
	for(int i = 0;i < h;i++)
	{
		for(int j = 0;j < w;j++)
		{
			sum += dfs(i,j);
		}
	}
	return sum;
}



int main()
{

	while(1)
	{
		cin >> w >> h;

		if(!w && !h)break;

		memset(f,0,50*50*sizeof(bool));
		memset(cell,0,50*50*sizeof(bool));

		for(int i = 0;i < h;i++)
		{
			for(int j = 0;j < w;j++)
			{
				cin >> cell[i][j];
			}
		}

		cout << cast() << endl;
	
	}

  return 0;
}

C++: #include <set>
#include <map>
#include <list>
#include <queue>
#include <stack>
#include <cmath>
#include <ctime>
#include <cstdio>
#include <vector>
#include <string>
#include <bitset>
#include <cctype>
#include <cstdlib>
#include <cstring>
#include <utility>
#include <numeric>
#include <complex>
#include <sstream>
#include <fstream>
#include <functional>
#include <iomanip>
#include <cassert>
#include <iostream>
#include <iterator>
#include <algorithm>
using namespace std;
typedef long long ll;
const double EPS = 1e-9;
typedef vector<int> vec;
typedef pair<int, int> P;
#define rep(n) REP(i, 0, n)
#define ALL(v) v.begin(), v.end()
#define out(a) cout << a << endl;
#define REP(i, x, n) for(int i = x; i < n; i++)
#define INF 100000000

int w, h;
int f[55][55] = { 0 };

void dfs(int y, int x) {
	for (int i = -1; i <= 1; i++) {
		for (int j = -1; j <= 1; j++) {
			int ny = y + i;
			int nx = x + j;
			if (0 <= ny&&ny < h && 0 <= nx&&nx < w&&f[ny][nx] == 1) {
				f[ny][nx] = 0;
				dfs(ny, nx);
			}
		}
	}
	return;
}

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

C++: #include <iostream>
#include <complex>
#include <sstream>
#include <string>
#include <algorithm>
#include <deque>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <vector>
#include <set>
#include <limits>
#include <cstdio>
#include <cctype>
#include <cmath>
#include <cstring>
#include <cstdlib>
#include <ctime>
using namespace std;
#define REP(i, j) for(int i = 0; i < (int)(j); ++i)
#define FOR(i, j, k) for(int i = (int)(j); i < (int)(k); ++i)
#define P pair<int, int>
#define SORT(v) sort((v).begin(), (v).end())
#define REVERSE(v) reverse((v).begin(), (v).end())
//#define int long long
const int MAX_HW = 55;

int H, W, v[MAX_HW][MAX_HW];
int my[] = {0, 0, 1, -1, 1, 1, -1, -1};
int mx[] = {1, -1, 0, 0, 1, -1, 1, -1};

void dfs(int y, int x){
  REP(i, 8){
    int ny = y + my[i], nx = x + mx[i];
    if(ny < 0 || nx < 0 || ny >= H || nx >= W || v[ny][nx] == 0) continue;
    v[ny][nx] = 0;
    dfs(ny, nx);
  }
}

int main() {
  while(cin >>W >>H && W){
    int ans = 0;
    REP(i, H) REP(j, W) cin >>v[i][j];
    REP(i, H){
      REP(j, W){
        if(v[i][j] == 1){
          ++ans;
          v[i][j] = 0;
          dfs(i, j);
        }
      }
    }
    cout <<ans <<endl;
  }
  return 0;
}