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<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);
					}

					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]] = 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];
}
}
*/

C++: #include<stdio.h>

#define R(q,n) for(int q=0; q<n; q++)
size_t m[50][50],W,H,i,j,a,c,d;

void f(int x, int y)
{
	m[x][y]=0;
	R(b,9)
	{
		c = x+b/3-1;
		d = y+b%3-1;

		if(c<W&&d<H&&m[c][d])
			f(c,d);
	}
}

main()
{
	while(scanf("%d%d",&W,&H),W&H)
	{
		a=0;
		R(i,H) R(j,W)
			scanf("%d", &m[j][i]);

		R(i,H) R(j,W)
		if(m[j][i]){
				f(j,i);
				a++;
		}
		printf("%d\n", a);
	}
}

C++: #include <bits/stdc++.h>
#define rep(i, a, b) for (int i = a; i < (b); i++)
#define rrep(i, a, b) for (int i = a; i >= (b); i--)
#define all(x) (x).begin(), (x).end()
using namespace std;
using ll = long long;
using P = pair<int, int>;
template <class T>
inline bool chmin(T& a, T b) {
   if (a > b) {
      a = b;
      return true;
   }
   return false;
}
template <class T>
inline bool chmax(T& a, T b) {
   if (a < b) {
      a = b;
      return true;
   }
   return false;
}
const int INF = 2e9;
const int MOD = 1e9 + 7;

int main() {
   while (true) {
      int w, h;
      cin >> w >> h;
      if (w == 0 && h == 0) break;
      vector<vector<int>> c(h, vector<int>(w)), a(h, vector<int>(w));

      rep(i, 0, h) rep(j, 0, w) cin >> c[i][j];
      int ans = 0;
      function<void(int, int)> dfs = [&](int u, int v) {
         if (a[v][u] != 0) return;
         c[v][u] = ans;
         a[v][u] = 1;
         rep(i, -1, 2) rep(j, -1, 2) {
            int x_i = u + i;
            int y_j = v + j;
            if (x_i >= 0 && x_i < w && y_j >= 0 && y_j < h && c[y_j][x_i] == 1)
               dfs(x_i, y_j);
         }
         return;
      };
      rep(i, 0, h) {
         rep(j, 0, w) {
            if (a[i][j] == 0 && c[i][j] == 1) {
               ans++;
               dfs(j, i);
            }
         }
      }
      cout << ans << endl;
   }
   return 0;
}

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

using namespace std;

inline bool inRange(int a, int x, int b) {
    return a <= x && x < b;
}

void fill(vector<vector<int> > &v, int r, int c) {
    queue<pair<int,int> > q;
    q.push(make_pair(r, c));
    v[r][c] = 0;
    while(!q.empty()) {
        const pair<int,int> cur = q.front();
        q.pop();
        for(int dr = -1; dr <= 1; ++dr) {
            for(int dc = -1; dc <= 1; ++dc) {
                int nr = cur.first + dr;
                int nc = cur.second + dc;
                if(inRange(0, nr, v.size()) && 
                   inRange(0, nc, v[0].size()) &&
                   v[nr][nc])
                {
                    v[nr][nc] = 0;
                    q.push(make_pair(nr, nc))
                }
            }
        }
    }
}

int main() {
    cin.tie(0);
    ios::sync_with_stdio(0);

    while(true) {
        int C, R;
        cin >> C >> R;
        if(!C && !R) break;

        vector<vector<int> > v(R, vector<int>(C));
        for(int i = 0; i < R; ++i) 
            for(int j = 0; j < C; ++j)
                cin >> v[i][j];

        int cnt = 0;
        for(int r = 0; r < R; ++r) {
            for(int c = 0; c < C; ++c) {
                if(v[r][c]) {
                    ++cnt;
                    fill(v, r, c);
                }
            }
        }

        cout << cnt << endl;
    }

    return 0;
}

C++: #include<stdio.h>
#include<iostream>
#include<algorithm>

#define rep(i,n) for(int i=0;i<(n);i++)

using namespace std;

int map[51][51];
int w,h;

void dfs(int x,int y) {
	map[x][y]=0;
	for(int i=-1;i<=1;i++) {
		for(int j=-1;j<=1;j++) {
			int nx = x+i;
			int ny = y+j;
			if(0<=nx&&nx<w && 0<=ny&&ny<h && map[nx][ny]==1)
				dfs(nx,ny);
		}
	}


}

void solve() {
	rep(i,51) rep(j,51) map[i][j]=0;

	rep(i,w) rep(j,h) cin>>map[i][j];

	int ans=0;
	rep(i,w) rep(j,h) {
		if(map[i][j]==1) {
			dfs(i,j);
			ans++;
		}
	}
	cout<<ans<<endl;
}

int main() {

	while (cin>>h>>w)
	{
		if(h+w==0) return 0;
		solve();

	}

	return 0;
}