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 "bits/stdc++.h"
#include "math.h"
 
using namespace std;
typedef long long ll;
typedef vector<ll> vll;
typedef vector<vll> vvll;
typedef vector<bool> vb;
typedef vector<vb> vvb;
typedef vector<int> vin;
typedef pair<ll,ll> P;
typedef vector<P> vp;
#define rep(i,a,b) for(ll i=(a);i<(b);++i)
#define SIZE(a) int((a).size())
#define out(a) cout<<(a)<<endl;
const int INF=INT_MAX;
const int MAX = 510000;
const ll MOD = 1000000007;
vin dx={-1,0,1},dy={-1,0,1};
ll w,h;
void dfs(vvll g,vvll &c,ll x,ll y){
  c[x][y]=1;
  rep(k,0,3){
    ll nx=x+dx[k];
    if(nx>=h||nx<0){continue;}
    rep(l,0,3){
      ll ny=y+dy[l];
      if(ny>=w||ny<0){continue;}
      if(!c[nx][ny]&&g[nx][ny]){
        dfs(g,c,nx,ny);
      }
    }
  }
}
int main(){
  do{
    ll cnt=0;
    cin>>w>>h;
    if(w==0&&h==0){break;}
    vvll g(h,vll(w)),c(h,vll(w,0));
    rep(i,0,h){
      rep(j,0,w){
        cin>>g[i][j];
      }
    }
    rep(i,0,h){
      rep(j,0,w){
        if(!c[i][j]&&g[i][j]){
          dfs(g,c,i,j);
          cnt++;
        }
      }
    }
   out(cnt);
  }while(w!=0&&h!=0);
}

C++: #include <bits/stdc++.h>
using namespace std;
#define REP(i, n) for(int i = 0; i < n; i++)
#define REPR(i, n) for(int i = n; i >= 0; i--)
#define FOR(i, m, n) for(int i = m; i < n; i++)
#define ALL(v) v.begin(), v.end()
#define CMAX(m, x)  m = max(m,x);
#define CMIN(m, x)  m = min(m,x);
#define itn int
typedef long long lint;
typedef long double ldouble;
const int INF = 1e9;
const lint LINF = 1e18;

int cnt = 0;
bool dfs(vector<vector<int> > &bi, vector<vector<int> > &flag,int x, int y){
    bool re = false;
    if(bi[y][x] == 1){
        if(flag[y][x] == 0){
            flag[y][x] = cnt;
            re = true;
            for(int i = -1;i <= 1; i++){
                for(int j = -1; j <= 1; j++){
                    dfs(bi,flag,x + i,y + j);
                }
            }
        }
    }
    return re;
}
int main(){
    int w, h;
    vector<int> ans;
    while(1){
        cin >> w >> h;
        if(w == 0 && h == 0)
            break;
        w += 2;
        h += 2;
        vector<vector<int> > bi(h,vector<int>(w));
        vector<vector<int> > flag(h,vector<int>(w,0));
        REP(i,h - 2){
            REP(j,w - 2)
                cin >> bi[i + 1][j + 1];
        }
        REP(i,h){
            bi[i][0] = 0;
            bi[i][w -1] = 0;
        }
        REP(i,w){
            bi[0][i] = 0;
            bi[h - 1][i] = 0;
        }
        REP(i,h){
            REP(j,w){
                if(bi[i][j] == 1 && flag[i][j] == 0){
                    cnt++;
                    if(!dfs(bi,flag,j,i)) cnt --;
                }
            }
        }
        ans.push_back(cnt);
        cnt = 0;
    }
    
    REP(i,ans.size())
        cout << ans[i] << endl;
    return 0;
}

C++: #define _CRT_SECURE_NO_WARNINGS
#define _USE_MATH_DEFINES

#include "bits/stdc++.h"
#define REP(i,a,b) for(i=a;i<b;++i)
#define rep(i,n) REP(i,0,n)
#define ll long long
#define ull unsigned ll
typedef long double ld;
#define ALL(a) (a).begin(),(a).end()
#define ifnot(a) if(not a)
#define dump(x)  cerr << #x << " = " << (x) << endl
using namespace std;

void reader(int &a) { scanf("%d", &a); }
void reader(double &a) { scanf("%lf", &a); }
void reader(char a[]) { scanf("%s", a); }
void reader(char &a) { scanf(" %c", &a); }
void reader(ll &a) { scanf("%lld", &a); }
void reader(ull &a) { scanf("%llu", &a); }
// void reader(string& a){cin >> a;};
template<class T, class U> void reader(T& t, U& u) { reader(t); reader(u); }
template<class T, class U, class V> void reader(T& t, U& u, V& v) { reader(t); reader(u); reader(v); }

void writer(const int a, char c) { printf("%d", a); putchar(c); }
void writer(const ll a, char c) { printf("%lld", a); putchar(c); }
void writer(const ull a, char c) { printf("%llu", a); putchar(c); }
void writer(const double a, char c) { printf("%.20lf", a); putchar(c); }
void writer(const char a[]) { printf("%s", a); };
void writer(const char a[], char c) { printf("%s", a); putchar(c); };
void writer(const char a, char c) { putchar(a); putchar(c); };
template<class T> void writerLn(T t) { writer(t, '\n'); }
template<class T, class U> void writerLn(T t, U u) { writer(t, ' '); writer(u, '\n'); }
template<class T, class U, class V> void writerLn(T t, U u, V v) { writer(t, ' '); writer(u, ' '); writer(v, '\n'); }
template<class T> void writerArr(T x[], int n) { int i; if (!n) { putchar('\n'); return; }rep(i, n - 1) writer(x[i], ' '); writer(x[n - 1], '\n'); }
template<class T> void writerVec(vector<T> x) { int n = x.size(); int i; if (!n) { putchar('\n'); return; }rep(i, n - 1) writer(x[i], ' '); writer(x[n - 1], '\n'); }

vector<string> split(const string &str, char sep) { vector<string> v; stringstream ss(str); string buffer; while (getline(ss, buffer, sep)) { v.push_back(buffer); }return v; }
// #define int ll
bool test = 1;
int dx[] = { 0,1,0,-1 };
int dy[] = { 1,0,-1,0 };
#define MAX MAX000
#define INF (1 << 28)
ull mod = (int)1e9 + 7;
//.....................

int W, H;
char c[100][100];
void grid_dfs(int y, int x) {
	int i, j;
	c[y][x] = '0';
	for (i = -1; i <= 1; i++) {
		for (j = -1; j <= 1; j++) {
			int nx = x + i;
			int ny = y + j;
			if (nx < 0 || W <= nx) continue;
			if (ny < 0 || H <= ny) continue;
			if (c[ny][nx] == '0') continue;
			grid_dfs(ny, nx);
		}
	}
}
signed main(void)
{
	int i, j, k;
	while (1) {
		cin >> W >> H;
		if (W == 0) continue;
		rep(i, H) rep(j, W) {
			reader(c[i][j]);
		}
		/*rep(i, H) {
			writerArr(c[i],W);
		}*/
		int cnt = 0;
		rep(i, H) rep(j, W) {
			if (c[i][j] == '1') {
				cnt++;
				grid_dfs(i, j);
			}
		}
		cout << cnt << endl;
	}
	return 0;
}