Go: package main

import (
	"bufio"
	"fmt"
	"io"
	"math"
	"os"
	"strconv"
)

var (
	readString func() string
	readBytes  func() []byte
	stdout     *bufio.Writer
)

func init() {
	readString, readBytes = newReadString(os.Stdin)
	stdout = bufio.NewWriter(os.Stdout)
}

func newReadString(ior io.Reader) (func() string, func() []byte) {
	r := bufio.NewScanner(ior)
	r.Buffer(make([]byte, 1024), math.MaxInt32)
	r.Split(bufio.ScanWords)

	f1 := func() string {
		if !r.Scan() {
			panic("Scan failed")
		}
		return r.Text()
	}
	f2 := func() []byte {
		return []byte(f1())
	}
	return f1, f2
}

func readInt() int {
	return int(readInt64())
}

func readInt64() int64 {
	i, err := strconv.ParseInt(readString(), 10, 64)
	if err != nil {
		panic(err.Error())
	}
	return i
}

func readFloat64() float64 {
	f, err := strconv.ParseFloat(readString(), 64)
	if err != nil {
		panic(err.Error())
	}
	return f
}

func printf(f string, args ...interface{}) (int, error) {
	return fmt.Fprintf(stdout, f, args...)
}

func println(args ...interface{}) (int, error) {
	return fmt.Fprintln(stdout, args...)
}

func eprintln(args ...interface{}) (int, error) {
	return fmt.Fprintln(os.Stderr, args...)
}

func eprintf(f string, args ...interface{}) (int, error) {
	return fmt.Fprintf(os.Stderr, f, args...)
}

func min(a, b int) int {
	if a < b {
		return a
	}
	return b
}

func min64(a, b int64) int64 {
	if a < b {
		return a
	}
	return b
}

func max(a, b int) int {
	if a < b {
		return b
	}
	return a
}

func max64(a, b int64) int64 {
	if a < b {
		return b
	}
	return a
}

func abs(a int) int {
	if a < 0 {
		return -a
	}
	return a
}

func abs64(a int64) int64 {
	if a < 0 {
		return -a
	}
	return a
}

func gcd(a, b int) int {
	if b == 0 {
		return a
	}
	return gcd(b, a%b)
}

func gcd64(a, b int64) int64 {
	if b == 0 {
		return a
	}
	return gcd64(b, a%b)
}

// readString() string
// readInt() int
// readInt64() int64
// readFloat64() float64

// -----------------------------------------------------------------------------

func main() {
	defer stdout.Flush()

	for {
		ans, ok := solve()
		if !ok {
			break
		}
		println(ans)
	}

}

func solve() (int, bool) {
	w := readInt()
	h := readInt()
	if w == 0 && h == 0 {
		return 0, false
	}

	c := make([][]int, h+2)
	c[0] = make([]int, w+2)
	c[h+1] = make([]int, w+2)
	for i := 1; i-1 < h; i++ {
		c[i] = make([]int, w+2)
		for j := 1; j-1 < w; j++ {
			c[i][j] = readInt()
		}
	}

	var ans int
	for i := 1; i-1 < h; i++ {
		for j := 1; j-1 < w; j++ {
			if 0 < c[i][j] {
				ans++
				dfs(c, i, j)
			}
		}
	}
	return ans, true
}

func dfs(c [][]int, y, x int) {
	c[y][x] = 0
	dx := []int{-1, 0, 1, -1, 1, -1, 0, 1}
	dy := []int{-1, -1, -1, 0, 0, 1, 1, 1}
	for i := range dx {
		nx := x + dx[i]
		ny := y + dy[i]
		if 0 < c[ny][nx] {
			dfs(c, ny, nx)
		}
	}
}

// -----------------------------------------------------------------------------

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

constexpr int MAX_H = 50;
constexpr int MAX_W = 50;

int H, W;
char grid[MAX_H][MAX_W];
bool reached[MAX_H][MAX_W];

#define OCTAS
#ifdef OCTAS
constexpr int dh[]{-1, -1, -1, 0, 0, +1, +1, +1};
constexpr int dw[]{-1, 0, +1, -1, +1, -1, 0, +1};
#else
constexpr int dh[]{-1, 0, 0, +1};
constexpr int dw[]{0, -1, +1, 0};
#endif

void dfs(int h, int w) {
  reached[h][w] = true;

  for (int i{}; i < sizeof(dh) / sizeof(int); ++i) {
    int nh = h + dh[i];
    if (nh < 0 || nh >= H)
      continue;
    int nw = w + dw[i];
    if (nw < 0 || nw >= W)
      continue;
    if (grid[nh][nw] == '0' || reached[nh][nw])
      continue;
    dfs(nh, nw);
  }
}

int main() {
  while (true) {
    cin >> H >> W;
    if (H == 0 && W == 0)
      break;
    fill(reached[0], reached[0] + MAX_H * MAX_W, false);
    for (int h{}; h < H; ++h) {
      for (int w{}; w < W; ++w) {
        cin >> grid[h][w];
      }
    }

    int island{};
    for (int h{}; h < H; ++h) {
      for (int w{}; w < W; ++w) {
        if (grid[h][w] == '0' || reached[h][w])
          continue;
        dfs(h, w);
        ++island;
      }
    }

    cout << island << endl;
  }

  return 0;
}

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

struct mapst {
	int x, y;
};

#define func(x,y) (c[y][x]&&!f[y][x])

int main() {
	int w, h, ans=0;
	int c[52][52]={{0}}, f[52][52]={{1}};
	int dx[8] = {-1, -1, 0, 1, 1, 1, 0, -1};
	int dy[8] = {0, -1, -1, -1, 0, 1, 1, 1};
	queue<mapst> q;
	while(1) {
		cin >> w >> h;
		if(!w&&!h) break;
		ans = 0;
		for(int i=1; i<=h; ++i) for(int j=1; j<=w; ++j) {
			cin >> c[i][j];
			f[i][j] = 0;
		}
		for(int i=1; i<=h; ++i) for(int j=1; j<=w; ++j) {
			if(func(j,i)) {
				mapst m = {j, i}, ms;
				q.push(m);
				ans++;
				do {
					m = q.front();
					q.pop();
					f[m.y][m.x] = 1;
					for(int k=0; k<8; k++) {
						if(func(m.x+dx[k],m.y+dy[k])) {
							ms.x = m.x+dx[k]; ms.y = m.y+dy[k];
							q.push(ms);
						}
					}
				}while(!q.empty());
			}
		}
		cout << ans << endl;
	}
}

C++: #include "bits/stdc++.h"
#define rep(i,n) for(int i=0;i<n;i++)
using namespace std;

using ll = long long;

int w, h, c[52][52];

void dfs(int i, int j) {
    c[i][j] = 0;
    for (int k = i - 1; k < i + 2; k++) {
        for (int l = j - 1; l < j + 2; l++) {
            if (c[k][l] == 1) dfs(k, l);
        }
    }
}

int main() {
    cin >> w >> h;
    while (w) {
        rep(i, 52) rep(j, 52) c[i][j] = 0;
        rep(i, h) rep(j, w) cin >> c[i + 1][j + 1];
        int ans = 0;
        rep(i, h + 2) rep(j, w + 2) {
            if (c[i][j] == 1) {
                dfs(i, j);
                ans++;
            }
        }
        cout << ans << "\n";
        cin >> w >> h;
    }
}

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

using namespace std;

int W, H;
int C[50][50];

void DFS(int h, int w)
{
    if (w < 0 || w >= W) return;
    if (h < 0 || h >= H) return;
    if (C[h][w] == 0) return;
    C[h][w] = 0;

    int dx[8] = {1, 1, 0, -1, -1, -1, 0, 1};
    int dy[8] = {0, 1, 1, 1, 0, -1, -1, -1};

    for (int i = 0; i < 8; ++i) {
        DFS(h+dx[i], w+dy[i]);
    }
}

int main()
{
    while (1) {
        cin >> W >> H;
        if (W == 0 && H == 0) {
            break;
        }

        for (int h = 0; h < H; ++h) {
            for (int w = 0; w < W; ++w) {
                cin >> C[h][w];
            }
        }

        int Res = 0;
        for (int h = 0; h < H; ++h) {
            for (int w = 0; w < W; ++w) {
                if (C[h][w] == 1) {
                    DFS(h, w);
                    ++Res;
                }
            }
        }
        cout << Res << endl;
    }

    return 0;
}

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


int main(void){

	int w, h;

	while (cin >> w >> h, w, h){
		int c[100][100] = { 0 };
		vector<bool> island;
		island.push_back(false);

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

		int count = 1;
		for (int j = 1; j <= h; j++){
			for (int i = 1; i <= w; i++){
				if (c[j][i] != 0){

					if (c[j][i - 1] != 0) c[j][i] = c[j][i - 1];
					else if (c[j - 1][i + 1] != 0) c[j][i] = c[j - 1][i + 1];
					else if (c[j - 1][i] != 0) c[j][i] = c[j - 1][i];
					else if (c[j - 1][i - 1] != 0) c[j][i] = c[j - 1][i - 1];
					else{
						c[j][i] = count;
						count++;
						island.push_back(true);
					}

					bool buff = island[c[j][i]];

					island[c[j][i - 1]] = island[c[j - 1][i + 1]] = island[c[j - 1][i]] = island[c[j - 1][i - 1]] = false;
					island[c[j][i]] = buff && true;

				}
			}
		}

		int result = 0;
		vector<bool>::iterator it;
		for (it = island.begin(); it != island.end(); ++it) 	if (*it == true) result++;
		
		cout << result << endl;

	}

	return 0;
}

/*
for(i=0;i<N;i++){
cin >> X[i];
}


for(i=0;i<N;i++){
for(j=0;j<N;j++){
cin >> X[i][j];
}
}
*/