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>
using namespace std;
#define MAX 50

int c[MAX][MAX];

void dfs(int w, int h, int x, int y);
int main(int argc, char const *argv[]){
    int w, h, ans;

    while (cin>>w>>h, w || h){
        ans = 0;
        for (int i = 0; i < h; i++){
            for (int j = 0; j < w; j++){
                cin>>c[i][j];
            }
        }
        for (int i = 0; i < h; i++){
            for (int j = 0; j < w; j++){
                if (c[i][j] == 1){
                    dfs(w, h, j, i);
                    ans++;
                }
            }
        }
        cout<<ans<<endl;
    }
    return 0;
}

void dfs(int w, int h, int x, int y){
    int dx[8] = {1, 1, 0, -1, -1, -1, 0, 1};
    int dy[8] = {0, 1, 1, 1, 0, -1, -1, -1};
    c[y][x] = 0;

    for (int i = 0; i < 8; i++){
        int nx = x + dx[i];
        int ny = y + dy[i];

        if (0 <= nx && nx < w && 0 <= ny && ny < h && c[ny][nx] == 1){
            dfs(w, h, nx, ny);
        }
    }
    return;
}

C++: #define _USE_MATH_DEFINES
#include<iostream>
#include<string>
#include<sstream>
#include<algorithm>
#include<numeric>
#include<cmath>
#include<bitset>
#include<map>
#include<set>
#include<vector>
#include<stack>
#include<queue>
#include<deque>
using namespace std;

void erase_island (int ocean[][50], int h, int w, int i, int j) {
    ocean[i][j] = 0;
    for(int dy = -1; dy <= 1; dy++) {
        for(int dx = -1; dx <= 1; dx++) {
            if (i + dy >= 0 && i + dy < h && j + dx >= 0 && j + dx < w) {
                if(ocean[i+dy][j+dx] == 1)  erase_island(ocean, h, w, i+dy, j+dx);
            }
        }
    }
}

int main() {

    int w, h;
    while(cin >> w >> h && (w || h)) {
        int ocean[h][50];
        for(int i = 0; i < h; i++) {
            for (int j = 0; j < w; j++) {
                cin >> ocean[i][j];
            }
        }
        int answer = 0;
        for(int i = 0; i < h; i++) {
            for(int j = 0; j < w; j++) {
                if (ocean[i][j] == 1) {
                    erase_island(ocean, h, w, i, j);
                    answer += 1;
                }
            }
        }
        cout << answer << endl;
    }
     
    return 0;
}

C++: #include <iostream>
#include <algorithm>

using namespace std;

int tizu[52][52];

void check(int i, int j) {
	tizu[i][j] = 0;
	for (int k = -1; k <= 1; k++) {
		for (int l = -1; l <= 1; l++) {
			if (tizu[i+k][j+l] == 1) {
				check(i+k,j+l);
			}
		}
	}
	return;
}

int main() {
	int w, h;
	while (cin >> w >> h) {
		if (w == 0 && h == 0) {
			break;
		}
		for (int i = 0; i < 52; i++) {
			for (int j = 0; j < 52; j++) {
				tizu[i][j] = 0;
			}
		}
		int counter = 0;
		for (int i = 1; i <= h; i++) {
			for (int j = 1; j <= w; j++) {
				cin >> tizu[i][j];
			}
		}
		for (int i = 1; i <= h; i++) {
			for (int j = 1; j <= w; j++) {
				if (tizu[i][j] == 1) {
					counter++;
					check(i,j);
				}
			}
		}
		cout << counter << endl;
	}
	return 0;
}

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

// 入力
int H, W;
vector<vector<int> > field;

// 探索
void dfs(int h, int w) {
    field[h][w] = 0;

    // 八方向を探索
    for (int dh = -1; dh <= 1; ++dh) {
        for (int dw = -1; dw <= 1; ++dw) {
            int nh = h + dh, nw = w + dw;
            
            // 場外アウトしたり、0 だったりはスルー
            if (nh < 0 || nh >= H || nw < 0 || nw >= W) continue;
            if (field[nh][nw] == 0) continue;

            // 再帰的に探索
            dfs(nh, nw);
        }
    }
}

int main() {
    // 入力受け取り
    while (cin >> W >> H) {
        if (H == 0 || W == 0) break;
        field.assign(H, vector<int>(W, 0));
        for (int h = 0; h < H; ++h) for (int w = 0; w < W; ++w) cin >> field[h][w];

        // 探索開始
        int count = 0;
        for (int h = 0; h < H; ++h) {
            for (int w = 0; w < W; ++w) {
                if (field[h][w] == 0) continue; // 残島じゃなかったらスルー
                dfs(h, w);
                ++count;
            }
        }
        cout << count << endl;
    }
}

C++: #include <bits/stdc++.h>
using namespace std;
using ll = long long;
constexpr ll MOD = 1000000007;
constexpr ll INF = 1ll<<60;

ll field[60][60];
bool f[60][60];
ll W, H;

void dfs(ll h, ll w)
{
	if (f[h][w]) return;
	f[h][w] = true;
	for (ll i = -1; i <= 1; ++i)
		for (ll j = -1; j <= 1; ++j)
		{
			ll nw = w + i;
			ll nh = h + j;
			if (nw < 0 || nw > W || nh < 0 || nh > H) continue;
			if (field[nh][nw])
				dfs(nh, nw);
		}
}

int main(int argc, char **argv)
{
	while (cin >> W >> H, true)
	{
		if (W == 0 && H == 0) break;
		memset(f, 0, sizeof f);
		memset(field, 0, sizeof field);

		vector<pair<ll, ll>> search;
		search.reserve(50*50);
		for (ll h = 0; h < H; ++h)
			for (ll w = 0; w < W; ++w)
			{
				cin >> field[h][w];
				if (field[h][w] == 1)
				{
					search.push_back(pair<ll, ll>(h, w));
					// std::cout << "(h, w) : " << h << ", " << w << std::endl;
				}
			}
		
		ll res{0};
		for (ll i = 0; i < (ll)search.size(); ++i)
		{
			if (!f[search[i].first][search[i].second])
			{
				// std::cout << "(h, w) : " << search[i].first << ", " << search[i].second << std::endl;
				dfs(search[i].first, search[i].second);
				++res;
			}
		}
		std::cout << res << std::endl;

	}
}