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++: #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;
}

C++:     #include<iostream>
    #include<stdio.h>
    //#include <bits/stdc++.h>
    #include<vector>
    #include<float.h>
    #include<iomanip>
    #include<algorithm>
    #include<string>
    #include<cstring>
    #include<math.h>
    #include<cmath>
    #include<sstream>
    #include<set>
    #include<map>
    #include<queue>
    #include<cassert>
    #include<cmath>
    #include<cstdint>
using namespace std;

bool seen[55][55];
vector<vector<int>> s(55, vector<int>(55));
int w, h;
void dfs(int y, int x){
    seen[y][x] = true;

    for(int i = -1; i <= 1; i++){
        for(int j = -1; j <= 1; j++){
            if(i == 0 && j == 0)continue;
            int ny = y + i, nx = x + j;
            
            if(ny < 0 || ny >= h || nx < 0 || nx >= w)continue;
            if(seen[ny][nx])continue;
            if(s[ny][nx] != 1)continue;
            dfs(ny, nx);
        }
    }
}
int main(){
    while(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 >> s[i][j];seen[i][j] = false;}
    int cnt = 0;
    for(int i = 0; i < h; i++){
        for(int j = 0; j < w; j++){
            if(seen[i][j])continue;
            if(s[i][j] == 0)continue;
            cnt++;
            dfs(i, j);
        }
    }
    cout << cnt << endl;
    }
}