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++: /**
 * code generated by JHelper
 * More info: https://github.com/AlexeyDmitriev/JHelper
 * @author champon
 */

#include <iostream>
#include <fstream>
#include<bits/stdc++.h>
#define se cout << "test ok" << endl;
#define sp << " " <<
#define enl "\n"
using namespace std;
using ll=long long;
using ld=long double;
ll mod = ll(1e9)+7;
ll inf = ll(1e18);
void bl(bool b, ostream& out=cout){ out << (b ? "Yes" : "No") << endl; }
void bl2(bool b, ostream& out=cout){ out << (b ? "YES" : "NO") << endl; }
template<typename T> inline bool chmax(T &a, T b){ if(a<b){a=b; return true;} return false; }
template<typename T> inline bool chmin(T &a, T b){ if(a>b){a=b; return true;} return false; }
int dx[] = {1, 0, -1, 0, 1, -1, 1, -1};
int dy[] = {0, 1, 0, -1, 1, -1, -1, 1};

#ifndef INCLUDE_DEBUG_HPP
#define INCLUDE_DEBUG_HPP

#include <iostream>
#include <vector>
#include <map>
using namespace std;

namespace dbg {
    using ll = long long;

    class Debug {
    public:
        Debug(){}
        template<typename T>
        void vd(vector<T> vec);
        template<typename T>
        void vd2(vector<vector<T>> vec);
        template<typename T>
        void ad(T *arr, ll n);
        template<typename T, size_t N>
        void ad2(T (&arr)[N], ll n);
        template<typename T>
        void md(T mp);
    };

    template<typename T>
    void Debug::vd(vector<T> vec) {
        for (auto vv : vec) cout << vv << " ";
        cout << endl;
    }

    template<typename T>
    void Debug::vd2(vector<vector<T>> vec) {
        for (auto vv : vec) {
            for (auto vvv : vv) cout << vvv << " ";
            cout << endl;
        }
    }

    template<typename T>
    void Debug::ad(T *arr, ll n) {
        for (int i = 0; i <= n; i++) cout << arr[i] << " ";
        cout << endl;
    }

    template<typename T, size_t N>
    void Debug::ad2(T (&arr)[N], ll n) {
        for (int i = 0; i <= N; i++) for (int j = 0; j <= n; j++) cout << arr[i][j] << " ";
        cout << endl;
    }

    template<typename T>
    void Debug::md(T mp) {
        cout << "key : value" << endl;
        for (auto const &m : mp) cout << m.first << " : " << m.second << endl;
        cout << endl;
    }

}

#endif //INCLUDE_DEBUG_HPP

using dbg::Debug;
Debug debug;

class a {
public:
    int w, h;
    vector<vector<int>> g;
    vector<vector<int>> visited;

    void dfs(int y, int x){
        visited[y][x] = 1;
        for(int i=0; i<8; i++){
            int ny = y + dy[i];
            int nx = x + dx[i];
            if(nx < 0 || ny < 0 || nx >= w || ny >= h) continue;
            if(!g[ny][nx] || visited[ny][nx]) continue;
            dfs(ny, nx);
        }
    }

	void solve(std::istream& in, std::ostream& out) {
        while(true) {
            in >> w >> h;
            if(!w && !h) break;
            g.assign(h, vector<int>(w));
            visited.assign(h, vector<int>(w, 0));

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

            ll cnt = 0;
            for(int i=0; i<h; i++){
                for(int j=0; j<w; j++){
                    if(visited[i][j] || !g[i][j]) continue;
                    dfs(i, j);
                    cnt++;
                }
            }

            out << cnt << enl;
        }
	}
};


int main() {
    cin.tie(nullptr);
    ios_base::sync_with_stdio(false);
	a solver;
	std::istream& in(std::cin);
	std::ostream& out(std::cout);
	solver.solve(in, out);
	return 0;
}

C++: #include <algorithm>
#include <cassert>
#include <cmath>
#include <cstdio>
#include <cstring>
#include <iomanip>
#include <iostream>
#include <map>
#include <memory>
#include <numeric>
#include <set>
#include <stack>
#include <string>
#include <vector>

#define INF 1000000000
#define MOD 1000000007
typedef long long ll;
typedef unsigned long long ull;
using namespace std;
#define int long long

struct Setup {
    Setup() {
        cin.tie(0);
        ios::sync_with_stdio(false);
        cout << fixed << setprecision(20);
    }
} SETUP;

vector<vector<int>> g_graph;
vector<vector<int>> g_visited;
int dy[] = {-1, -1, -1, 0, 0, 1, 1, 1};
int dx[] = {-1, 0, 1, -1, 1, -1, 0, 1};

void dfs(int y, int x, int h, int w) {
    g_visited[y][x] = true;
    for (int i = 0; i < 8; i++) {
        int ny = y + dy[i], nx = x + dx[i];
        if (ny < 0 || ny >= h || nx < 0 || nx >= w) {
            continue;
        }
        if (g_visited[ny][nx]) {
            continue;
        }
        if (g_graph[ny][nx] == 0) {
            continue;
        }
        dfs(ny, nx, h, w);
    }
}

void go(int y, int x, int h, int w, int &island) {
    if (g_visited[y][x]) {
        return;
    }
    if (g_graph[y][x] == 0) {
        return;
    }
    dfs(y, x, h, w);
    island += 1;
}

void solve(int h, int w) {
    g_graph.assign(h, vector<int>(w, 0));
    g_visited.assign(h, vector<int>(w, 0));
    for (int i = 0; i < h; i++) {
        for (int j = 0; j < w; j++) {
            cin >> g_graph[i][j];
        }
    }

    int island = 0;
    for (int i = 0; i < h; i++) {
        for (int j = 0; j < w; j++) {
            go(i, j, h, w, island);
        }
    }
    cout << island << endl;
}

signed main() {
    while (1) {
        int w, h;
        cin >> w >> h;
        if (w == 0 && h == 0) {
            return 0;
        } else {
            solve(h, w);
        }
    }
}