Go: package main

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

var (
	readString func() string
	readBytes  func() []byte
	stdout     *bufio.Writer
)

func init() {
	readString, readBytes = newReadString(os.Stdin)
	stdout = bufio.NewWriter(os.Stdout)
}

func newReadString(ior io.Reader) (func() string, func() []byte) {
	r := bufio.NewScanner(ior)
	r.Buffer(make([]byte, 1024), math.MaxInt32)
	r.Split(bufio.ScanWords)

	f1 := func() string {
		if !r.Scan() {
			panic("Scan failed")
		}
		return r.Text()
	}
	f2 := func() []byte {
		return []byte(f1())
	}
	return f1, f2
}

func readInt() int {
	return int(readInt64())
}

func readInt64() int64 {
	i, err := strconv.ParseInt(readString(), 10, 64)
	if err != nil {
		panic(err.Error())
	}
	return i
}

func readFloat64() float64 {
	f, err := strconv.ParseFloat(readString(), 64)
	if err != nil {
		panic(err.Error())
	}
	return f
}

func printf(f string, args ...interface{}) (int, error) {
	return fmt.Fprintf(stdout, f, args...)
}

func println(args ...interface{}) (int, error) {
	return fmt.Fprintln(stdout, args...)
}

func eprintln(args ...interface{}) (int, error) {
	return fmt.Fprintln(os.Stderr, args...)
}

func eprintf(f string, args ...interface{}) (int, error) {
	return fmt.Fprintf(os.Stderr, f, args...)
}

func min(a, b int) int {
	if a < b {
		return a
	}
	return b
}

func min64(a, b int64) int64 {
	if a < b {
		return a
	}
	return b
}

func max(a, b int) int {
	if a < b {
		return b
	}
	return a
}

func max64(a, b int64) int64 {
	if a < b {
		return b
	}
	return a
}

func abs(a int) int {
	if a < 0 {
		return -a
	}
	return a
}

func abs64(a int64) int64 {
	if a < 0 {
		return -a
	}
	return a
}

func gcd(a, b int) int {
	if b == 0 {
		return a
	}
	return gcd(b, a%b)
}

func gcd64(a, b int64) int64 {
	if b == 0 {
		return a
	}
	return gcd64(b, a%b)
}

// readString() string
// readInt() int
// readInt64() int64
// readFloat64() float64

// -----------------------------------------------------------------------------

func main() {
	defer stdout.Flush()

	for {
		ans, ok := solve()
		if !ok {
			break
		}
		println(ans)
	}

}

func solve() (int, bool) {
	w := readInt()
	h := readInt()
	if w == 0 && h == 0 {
		return 0, false
	}

	c := make([][]int, h+2)
	c[0] = make([]int, w+2)
	c[h+1] = make([]int, w+2)
	for i := 1; i-1 < h; i++ {
		c[i] = make([]int, w+2)
		for j := 1; j-1 < w; j++ {
			c[i][j] = readInt()
		}
	}

	var ans int
	for i := 1; i-1 < h; i++ {
		for j := 1; j-1 < w; j++ {
			if 0 < c[i][j] {
				ans++
				dfs(c, i, j)
			}
		}
	}
	return ans, true
}

func dfs(c [][]int, y, x int) {
	c[y][x] = 0
	dx := []int{-1, 0, 1, -1, 1, -1, 0, 1}
	dy := []int{-1, -1, -1, 0, 0, 1, 1, 1}
	for i := range dx {
		nx := x + dx[i]
		ny := y + dy[i]
		if 0 < c[ny][nx] {
			dfs(c, ny, nx)
		}
	}
}

// -----------------------------------------------------------------------------

C++: #include "bits/stdc++.h"

#define REP(i,num) for(ll i=0;i<(num);++i)
#define LOOP(i) while(i--)
#define ALL(c) c.begin(),c.end()
#define PRINTALL(c) for(auto pitr=c.begin();pitr!=c.end();++pitr){cout<<*pitr;if(next(pitr,1)!=c.end())cout<<' ';}cout<<endl;
#define PAIRCOMP(c,comp) [](const pair<ll,ll>& lhs,const pair<ll,ll>& rhs){return lhs.c comp rhs.c;}

using namespace std;
using ll = long long;

constexpr ll atcoder_mod = 1e9+7;

template<typename T=ll>
T in(){T x; cin >> x; return (x);}
template<typename T=ll,typename C=vector<T>>
C vecin(int N){C x(N);REP(i,N){x[i]=in<T>();}return move(x);}

void vout(){cout << endl;}
template<typename Head,typename... Tail>
void vout(Head&& h,Tail&&... t){cout << ' ' << h;vout(forward<Tail>(t)...);}
void out(){cout << endl;}
template<typename Head,typename... Tail>
void out(Head&& h,Tail&&... t){cout << h;vout(forward<Tail>(t)...);}

class ConnectNodeInfo{
	vector<vector<pair<ll,ll>>> graph;
public:
	ConnectNodeInfo(int node_num){
		graph.resize(node_num);
	}
	void AddNonDirectionalConnection(ll u,ll v,ll w){
		graph[u].emplace_back(v,w);
		graph[v].emplace_back(u,w);
	}
	void AddDirectionalConnection(ll u,ll v,ll w){
		graph[u].emplace_back(v,w);
	}
	vector<pair<ll,ll>>& operator[](ll index){
		return graph[index];
	}
	size_t size(){return graph.size();}
};

vector<int> D,F;

int dfs(int p,int num,int H,int W,vector<vector<int>>& M,vector<vector<int>>& D){
	int u=p%W,v=p/W;
	D[v][u] = num;
	if(u>0 && M[v][u-1] && D[v][u-1]==-1){
		dfs(u-1+v*W,num,H,W,M,D);
	}
	if(u<W-1 && M[v][u+1] && D[v][u+1]==-1){
		dfs(u+1+v*W,num,H,W,M,D);
	}
	if(v>0 && M[v-1][u] && D[v-1][u]==-1){
		dfs(u+(v-1)*W,num,H,W,M,D);
	}
	if(v<H-1 && M[v+1][u] && D[v+1][u]==-1){
		dfs(u+(v+1)*W,num,H,W,M,D);
	}

	if(u>0 && v>0 && M[v-1][u-1] && D[v-1][u-1]==-1){
		dfs(u-1+(v-1)*W,num,H,W,M,D);
	}
	if(u<W-1 && v<H-1 && M[v+1][u+1] && D[v+1][u+1]==-1){
		dfs(u+1+(v+1)*W,num,H,W,M,D);
	}
	if(v>0 && u<W-1 && M[v-1][u+1] && D[v-1][u+1]==-1){
		dfs(u+1+(v-1)*W,num,H,W,M,D);
	}
	if(v<H-1 && u>0 && M[v+1][u-1] && D[v+1][u-1]==-1){
		dfs(u-1+(v+1)*W,num,H,W,M,D);
	}
	return 0;
}

int main(){
	cin.tie(0);
	ios::sync_with_stdio(false);
	cout<<fixed<<setprecision(10);

	while(true){
		int W=in(),H=in();
		if(!W && !H) break;

		vector<vector<int>> M(H,vector<int>(W,0)),D(H,vector<int>(W,-1));
		REP(i,H){
			REP(j,W){
				M[i][j]=in();
			}
		}

		int num=0;
		REP(i,H){
			REP(j,W){
				if(M[i][j] && D[i][j]==-1){
					dfs(j+i*W,++num,H,W,M,D);
				}
			}
		}
		out(num);
	}

	return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
enum class WalkingResult { undef, walked };
enum class LandS { sea, land };
using LMap = vector<vector<LandS>>;

void solve(int w, int h) {
    LMap lMap(h, vector<LandS>(w));
    vector<pair<int, int>> lands;
    for (int i = 0; i < h; ++i) {
        for (int j = 0; j < w; ++j) {
            int t;
            cin >> t;
            lMap[i][j] = t == 1 ? LandS::land : LandS::sea;
            if (t == 1) lands.push_back(make_pair(i, j));
        }
    }

    vector<vector<WalkingResult>> wMap(h, vector<WalkingResult>(w, WalkingResult::undef));
    int count = 0;
    stack<pair<int, int>> s;
    for (int i = 0; i < lands.size(); ++i) {
        pair<int, int> x = lands[i];
        bool already = wMap[x.first][x.second] == WalkingResult::walked;
        if (already) continue;
        s.push(x);
        while(!s.empty()) {
            pair<int, int> pos = s.top();
            s.pop();
            bool out = pos.first < 0 || h <= pos.first || pos.second < 0 || w <= pos.second;
            if (out) continue;
            bool sea = lMap[pos.first][pos.second] == LandS::sea;
            bool walked = wMap[pos.first][pos.second] == WalkingResult::walked;
            if (sea || walked) continue;
            wMap[pos.first][pos.second] = WalkingResult::walked;
            s.push(make_pair(pos.first + 1, pos.second));
            s.push(make_pair(pos.first - 1, pos.second));
            s.push(make_pair(pos.first, pos.second + 1));
            s.push(make_pair(pos.first, pos.second - 1));
            s.push(make_pair(pos.first - 1, pos.second - 1));
            s.push(make_pair(pos.first + 1, pos.second - 1));
            s.push(make_pair(pos.first - 1, pos.second + 1));
            s.push(make_pair(pos.first + 1, pos.second + 1));
        }
        count++;
    }
    cout << count << endl;
}

int main() {

    while (true) {
        int w, h;
        cin >> w >> h;
        if (w == 0 && h == 0) break;
        solve(w, h);
    }
    return 0;
}