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++: //8方向
//0が海、1が島

#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) {
			//if(dh*dw!=0) continue; //4方向にするときはここを有効に
			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<iostream>
#include<algorithm>
#include<cmath>
#include<iomanip>
#include<map>
using namespace std;
int w,h,c[50][50];

void dfs(int y,int x) {
  c[y][x]=0;
  for(int dy=-1; dy<=1; dy++) {
    for(int dx=-1; dx<=1; dx++) {
      int nx=x+dx,ny=y+dy;
      if(nx>=0&&nx<w&&ny>=0&&ny<h&&c[ny][nx]==1) {
        dfs(ny,nx);
      }
    }
  }
}
int main() {
  while(cin >> w >> h) {
    if(w==0&&h==0) {
      return 0;
    }
    else {
      int 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(i,j);
            ans++;
          }
        }
      }
      cout << ans << endl;
    }
  }
}