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++: /*
URL: http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=1160&lang=jp
?????????: How Many Islands?
?????°:
18:49 ?????????????????????????§£?????????
*/
#include <iostream>
using namespace std;

int dat[52][52]; // ??¨?????????1???????????£?????°

void delete_island_from(int i, int j)
{
	int dx[8] = {-1,-1,-1, 0,  0, 1, 1, 1};
	int dy[8] = {-1, 0, 1,-1,  1,-1, 0, 1};

	dat[i][j] = 0;
	for(int k=0;k<8;k++) {
		if(dat[i+dx[k]][j+dy[k]]) {
			delete_island_from(i+dx[k],j+dy[k]);
		}
	}
}


int main()
{
	while(true){ // data set
		//dat???0????????¢
		for(int i=0;i<52;i++){
			for(int j=0;j<52;j++){
				dat[i][j]=0;
			}
		}

		int w; int h;
		cin >> w >> h;
		if(w == 0 && h == 0) {break;}

		for(int i=0; i<h;i++) {
			for(int j=0;j<w;j++) {
				cin >> dat[i+1][j+1]; // ??¨?????????1???????????£?????°
			}
		}

		int ans = 0;
		while(true) {
			for(int i=0; i<h+2;i++) { // ????????£?????°??????
				for(int j=0;j<w+2;j++) {
					if(dat[i][j] == 1){
						delete_island_from(i,j);
						ans++;
						goto label1;
					}
				}
			} // all is ocean
			cout << ans << endl;
			break;


			label1: ;
		}
	}
}

C++: #include <bits/stdc++.h>
using namespace std;

int main() {
    while (true) {
        bool seen[100][100] = {false};
        vector<vector<int>> field;
        stack<pair<int, int>> to_visit;
        int cnt = 0;

        int w, h;
        cin >> w >> h;

        if (w == 0 || h == 0) {
            break;
        }

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

        // for (int i = 0; i < h; i++) {
        //     for (int j = 0; j < w; j++) {
        //         if (field[i][j] == 0) {
        //             cout << "^";
        //         }
        //         else {
        //             cout << "O";
        //         }
        //     }
        //     cout << endl;
        // }

        for (int i = 0; i < h; i++) {
            for (int j = 0; j < w; j++) {
                if (field[i][j] == 0) {
                    continue;
                }
                if (seen[i][j] == true) {
                    continue;
                }

                cnt++;
                to_visit.push(make_pair(i, j));
                seen[i][j] = true;
                while (to_visit.empty() == false) {
                    pair<int, int> cur_pos = to_visit.top(); to_visit.pop();
                    int cur_h = cur_pos.first;
                    int cur_w = cur_pos.second;
                    for (int dh = -1; dh <= 1; dh++) {
                        for (int dw = -1; dw <= 1; dw++) {
                            if (dh == 0 && dw == 0) {
                                continue;
                            }

                            int next_h = cur_h + dh;
                            int next_w = cur_w + dw;
                            if (next_h < 0 || next_h >= h || next_w < 0 || next_w >= w) {
                                continue;
                            }
                            if (seen[next_h][next_w] == true) {
                                continue;
                            }
                            if (field[next_h][next_w] == 0) {
                                continue;
                            }
                            to_visit.push(make_pair(next_h, next_w));
                            seen[next_h][next_w] = true;
                        }
                    }
                }
            }
        }

        cout << cnt << endl;
    }

    return 0;
}

C++: #include <iostream>
#include <cstdio>
#include <cstdlib>

using namespace std;

#define MAX_L 50

int graph[MAX_L+2][MAX_L+2];

void search(int x, int y, int num){
	graph[x][y]=num;
	for(int i=-1; i<=1; i++){
	    for(int j=-1; j<=1; j++){
	      if(graph[x+i][y+j] == 1){search(x+i, y+j, num);}
	    }
	}
}

int main()
{
	int w, h, label;
 
	while(true){
		scanf("%d%d\n",&w, &h);
		if(w==0 && h==0){return 0;}

		for(int i=0; i<h+2; i++){
			for(int j=0; j<w+2; j++){
				graph[i][j]=0;
			}
		}

		for(int i=1; i<h+1; i++){
			for(int j=1; j<w+1; j++){
				cin >> graph[i][j];
			}
		}

		label = 1;
		for(int i=1; i<h+1; i++){
			for(int j=1; j<w+1; j++){
				if(graph[i][j]==1){
					label++;
					search(i,j,label);
				}
			}
		}
		cout << label-1 << endl;		
	}	
}