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>
//#include<>

using namespace std;

struct Node{

	Node();

	int aLandType;

};

Node::Node(){
	aLandType = 0;
}

bool check(const int x, const int y, const int LandNum, const int aNodeCol[50][50], const int aXMax, const int aYMax){
	if ((x<0 || x >= aXMax) || (y<0 || y >= aYMax) || (aNodeCol[x][y] != 1)){
		return false;
	}
	return true;
}
bool LandConfirmedAndMawariCheck(const int x, const int y, const int LandNum, int aNodeCol[50][50], const int aXMax, const int aYMax){
	if (aNodeCol[x][y] == 1){
		aNodeCol[x][y] = LandNum;
		/*if (check(x - 1, y, LandNum, aNodeCol, aXMax, aYMax))LandConfirmedAndMawariCheck(x - 1, y, LandNum, aNodeCol, aXMax, aYMax);
		if (check(x - 1, y - 1, LandNum, aNodeCol, aXMax, aYMax))LandConfirmedAndMawariCheck(x - 1, y - 1, LandNum, aNodeCol, aXMax, aYMax);
		if (check(x - 1, y + 1, LandNum, aNodeCol, aXMax, aYMax))LandConfirmedAndMawariCheck(x - 1, y + 1, LandNum, aNodeCol, aXMax, aYMax);
		if (check(x + 1, y - 1, LandNum, aNodeCol, aXMax, aYMax))LandConfirmedAndMawariCheck(x + 1, y - 1, LandNum, aNodeCol, aXMax, aYMax);
		if (check(x + 1, y, LandNum, aNodeCol, aXMax, aYMax))LandConfirmedAndMawariCheck(x + 1, y, LandNum, aNodeCol, aXMax, aYMax);
		if (check(x + 1, y + 1, LandNum, aNodeCol, aXMax, aYMax))LandConfirmedAndMawariCheck(x + 1, y + 1, LandNum, aNodeCol, aXMax, aYMax);
		if (check(x, y - 1, LandNum, aNodeCol, aXMax, aYMax))LandConfirmedAndMawariCheck(x, y - 1, LandNum, aNodeCol, aXMax, aYMax);
		if (check(x, y + 1, LandNum, aNodeCol, aXMax, aYMax))LandConfirmedAndMawariCheck(x, y + 1, LandNum, aNodeCol, aXMax, aYMax);*/
		if (!(x - 1<0 || x - 1 >= aXMax) || (y    <0 || y     >= aYMax) || (aNodeCol[x-1][y    ] != 1))LandConfirmedAndMawariCheck(x - 1, y    , LandNum, aNodeCol, aXMax, aYMax);
		if (!(x - 1<0 || x - 1 >= aXMax) || (y - 1<0 || y - 1 >= aYMax) || (aNodeCol[x-1][y - 1] != 1))LandConfirmedAndMawariCheck(x - 1, y - 1, LandNum, aNodeCol, aXMax, aYMax);
		if (!(x - 1<0 || x - 1 >= aXMax) || (y + 1<0 || y + 1 >= aYMax) || (aNodeCol[x-1][y + 1] != 1))LandConfirmedAndMawariCheck(x - 1, y + 1, LandNum, aNodeCol, aXMax, aYMax);
		if (!(x + 1<0 || x + 1 >= aXMax) || (y - 1<0 || y - 1 >= aYMax) || (aNodeCol[x+1][y - 1] != 1))LandConfirmedAndMawariCheck(x + 1, y - 1, LandNum, aNodeCol, aXMax, aYMax);
		if (!(x + 1<0 || x + 1 >= aXMax) || (y    <0 || y     >= aYMax) || (aNodeCol[x+1][y    ] != 1))LandConfirmedAndMawariCheck(x + 1, y    , LandNum, aNodeCol, aXMax, aYMax);
		if (!(x + 1<0 || x + 1 >= aXMax) || (y + 1<0 || y + 1 >= aYMax) || (aNodeCol[x+1][y + 1] != 1))LandConfirmedAndMawariCheck(x + 1, y + 1, LandNum, aNodeCol, aXMax, aYMax);
		if (!(x    <0 || x     >= aXMax) || (y - 1<0 || y - 1 >= aYMax) || (aNodeCol[x  ][y - 1] != 1))LandConfirmedAndMawariCheck(x    , y - 1, LandNum, aNodeCol, aXMax, aYMax);
		if (!(x    <0 || x     >= aXMax) || (y + 1<0 || y + 1 >= aYMax) || (aNodeCol[x  ][y + 1] != 1))LandConfirmedAndMawariCheck(x    , y + 1, LandNum, aNodeCol, aXMax, aYMax);
		return true;
	}
	return false;
}



int main(void){
	int NodeCol[50][50];
	int a, b, c;
	int XMax, YMax;
	while(1){
		cin >> a >> b;
		if (a == b == 0)break;
		XMax = a; YMax = b;

		for (int Lone = 0;  Lone < XMax; ++Lone){
			for (int Ltwo = 0; Ltwo < YMax; ++Ltwo){
				cin >> c;
				NodeCol[Lone][Ltwo] = c;
			}
		}
		int t = 2;
		for (int Lone = 0;  Lone < XMax; ++Lone){
			for (int Ltwo = 0; Ltwo < YMax; ++Ltwo){
				if (NodeCol[Lone][Ltwo]==1)
				{
					if (LandConfirmedAndMawariCheck(Lone, Ltwo, t, NodeCol, XMax, YMax))t++;
				}
			}
		}
		cout << t-2<<endl;
	}
	return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define INF (1LL<<50)
#define MOD 1000000007

typedef vector<vector<int>> Graph;
int x[] = {-1,-1,-1,0,0,0,1,1,1};
int y[] = {-1,0,1,-1,0,1,-1,0,1};
int W,H;
Graph C(51,vector<int>(51));
Graph seen(51,vector<int>(51));

void dfs(Graph &C, Graph &seen, int h, int w){
    seen[h][w] = 1;
    rep(i,9){
        int next_h,next_w;
        next_h = h+y[i];
        next_w = w+x[i];
        if(next_h<0||next_h>=H||next_w<0||next_w>=W)continue;
        if(C[next_h][next_w]==1&&seen[next_h][next_w]==0){
            dfs(C,seen,next_h,next_w);
        }
    }
}

int main(){
    while(true){
        cin >> W >> H;
        if(W==0&&H==0){
            return 0;
        }
        rep(i,H)rep(j,W){
            cin >> C[i][j];
            seen[i][j]=0;
        } 
        int num=0;
        rep(i,H){
            rep(j,W){
                if(C[i][j]==0 || seen[i][j]==1) continue;
                num++;
                dfs(C,seen,i,j);
            }
        }
        cout << num << endl;
    }
    return 0;
}