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;

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

// 探索
void dfs(int h, int w) {
    field[h][w] = 0;
    for (int dh = -1; dh <= 1; ++dh) {
        for (int dw = -1; dw <= 1; ++dw) {
            int nh = h + dh, nw = w + dw;
            if (nh < 0 || nh >= H || nw < 0 || nw >= W) continue;
            if (field[nh][nw] == 0) continue;
            dfs(nh, nw);
        }
    }
}

int main() {
    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];
        
        int count = 0;
        for (int h = 0; h < H; ++h) {
            for (int w = 0; w < W; ++w) {
                if (field[h][w] == 0) continue; 
                dfs(h, w);
                ++count;
            }
        }
        cout << count << endl;
    }
}

C++: #include <iostream>
using namespace std;
 
int main(void){
    while (1) {
        int Y, X;
        int c[55][55];
        cin >> X >> Y;
         
        //終了
        if (Y == 0 && X == 0) break;
         
        for (int i = 1; i <= Y; i++) {
            for (int j = 1; j <= X; j++) cin >> c[i][j];
        }
         
        //深さ別にリストを作成
        int vy[2555][155], vx[2555][155], pl[2555];
        for (int i = 0; i < 2000; i++) {
            pl[i] = 0;
            vy[i][0] = vx[i][0] = -1;
            for (int j = 1; j <= 553; j++) {
                vy[i][j] = vx[i][j] = 0;
            }
        }  
 
        //移動方向の指定
        int dy[8] = {1, 0, -1, 0, 1, 1, -1, -1};
        int dx[8] = {0, 1, 0, -1, 1, -1, 1, -1};
     
        //通過済みかどうか
        bool psd[55][55];
        
        for (int i = 0; i <= 53; i++) {
            for (int j = 0; j <= 53; j++) psd[i][j] = false;
        }
        
        for (int i = 1; i <= Y; i++) {
            for (int j = 1; j <= X; j++) {
                psd[i][j] = true;
                if (c[i][j] == 0) psd[i][j] = false;
            }
        }
         
        for (int i = 0; i <= Y + 1; i++) psd[i][0] = psd[i][X + 1] = false;
        for (int i = 0; i <= X + 1; i++) psd[0][i] = psd[Y + 1][i] = false;
         
        bool fns = false;
        int isl = 0;
        while (1) {
            for (int inf = 0; true; inf++) {
                bool spot = false;
                if (inf == 0) {
                    vy[0][0] = -1;
                    for (int i = 1; i <= Y; i++) {
                        for (int j = 1; j <= X; j++) {
                            if (psd[i][j] == true) {
                                vy[0][0] = i;
                                vx[0][0] = j;
                                isl++;
                                pl[0] = 1;
                                psd[i][j] = false;
                                spot = true;
                                break;
                            }
                        }
                        if (spot) break;
                    }
                    if (vy[0][0] == -1) {
                        fns = true;
                        break; //4, 全部の島の確認終了
                    }
                }
                else {
                    int pt = 0;
                    for (int i = 0; i < pl[inf - 1]; i++) {
                        for (int dir = 0; dir < 8; dir++) {
                            
                            if (vy[inf - 1][i] + dy[dir] != -1 && vy[inf - 1][i] + dy[dir] != Y + 2 && vx[inf - 1][i] + dx[dir] != -1 && vx[inf - 1][i] + dx[dir] != X + 2) {
                                if (psd[vy[inf - 1][i] + dy[dir]][vx[inf - 1][i] + dx[dir]] == true) {
                                    vy[inf][pt] = vy[inf - 1][i] + dy[dir];
                                    vx[inf][pt] = vx[inf - 1][i] + dx[dir];
                                    pl[inf]++;
                                    psd[vy[inf][pt]][vx[inf][pt]] = false;
                                    pt++;
                                }
                            }
                        }
                    }
                    if (pt == 0) break; //4, 1つの島の確認終了
                }
//                cout << "*" << inf << endl;
//                for (int i = 0; i < pl[inf]; i++) cout << vy[inf][i] << ", " << vx[inf][i] << endl;
            }
            if (fns) {
                cout << isl << endl;
                break; // 2, query終了
            }
        }
    }
}