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 <algorithm>
#include <stack>
using namespace std;

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

struct Data {
	int x, y, n;
};

int w, h;
int c[51][51];
stack<Data> st;

void land_dfs(int x, int y, int n) {
	

	c[x][y] = n;

	// 島の発見中
	// 周囲8マスに島チェック

	for (int yy = -1; yy <= 1; yy++) {
		for (int xx = -1; xx <= 1; xx++) {
			if (x + xx < 0 || x + xx >(w - 1)) continue;
			if (y + yy < 0 || y + yy >(h - 1)) continue;
			if (c[x + xx][y + yy] != 1) continue;

				st.push({ x + xx, y + yy, n });

		}
	}

}

int main() {

	while (true) {
		cin >> w >> h;
		if (w == 0 &&  h == 0) break;

		int count = 0;

		for (int y = 0; y < h; y++) {
			for (int x = 0; x < w; x++) {
				cin >> c[x][y];
			}
		}

		for (int y = 0; y < h; y++) {
			for (int x = 0; x < w; x++) {
				if (c[x][y] == 1) {
					count++;
					st.push({ x, y, count + 1 });


					while (!st.empty()) {
						const auto d = st.top();
						st.pop();
						land_dfs(d.x, d.y, d.n);
					}
				}
			}
		}

		cout << count << endl;
	}


	return 0;
}

C++: #include <bits/stdc++.h>

using namespace std;

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

void dfs(int x, int y, vector<vector<bool> >& Cango){
  
  Cango[x][y] = false;
  

  for(int i = 0; i < 8; i++){
    int nextx = x + dx[i];
    int nexty = y + dy[i];
    
    if(Cango[nextx][nexty]) dfs(nextx, nexty, Cango);

  }
}

int main(void)
{
  
  int w, h;
  int si, sj;
  while(1){
    cin >> w >> h;
    if(w == 0 && h == 0) break;

    vector<vector<bool> > Cango(h + 2, vector<bool>(w + 2, false));
    for(int i = 1 ; i <= h; i++){
      for(int j = 1; j <= w; j++){
	int input; cin >> input;
       Cango[i][j] = input;
      }
    }
    
    int counter = 0;

    for(int i = 1; i <= h; i++){
      for(int j = 1; j <= w; j++){
        if(Cango[i][j] == true){
          counter++;
           dfs(i, j, Cango);
         }
       }
     }
    cout << counter << endl;
  }

  return 0;
    
}

C++: #include<iostream>
#include<iomanip>
#include<cstdlib>
#include<stdio.h>
#include<time.h>
#include<math.h>
#include<algorithm>
#include<string>
#include<vector>
#include<list>
#include<queue>
#include<stack>
#include<deque>
#include<set>
#include<map>
#define REP(i, N) for(ll i = 0; i < N; ++i)
#define FOR(i, a, b) for(ll i = a; i < b; ++i)
#define ALL(a) (a).begin(),(a).end()
#define pb push_back
#define INF 1000000000
#define MOD 1000000007
using namespace std;
typedef long long ll;
typedef pair<ll, ll> P;
int dx[4] = {1, 0, -1, 0};
int dy[4] = {0, 1, 0, -1};
int qx[8] = {1, 1, 0, -1, -1, -1, 0, 1};
int qy[8] = {0, 1, 1, 1, 0, -1, -1, -1};

vector<vector<int> > m;
int w, h;

void cal(ll x, ll y) {
	REP(i, 8) {
		ll nx = x + qx[i];
		ll ny = y + qy[i];
		if(nx >= 0 && nx < h && ny >= 0 && ny < w && m[nx][ny] == 1) {
			m[nx][ny] = 0;
			cal(nx, ny);
		}
	}
}

int main(void) {
	while(true) {
		cin>>w>>h;
		if(w == 0 && h == 0) break;
		m.resize(h);
		REP(i, h) {
			m[i].resize(w);
		}
		REP(i, h) {
			REP(j, w) {
				cin>>m[i][j];
			}
		}
		ll ans = 0;
		REP(i, h) {
			REP(j, w) {
				if(m[i][j] == 1) {
					++ans;
					cal(i, j);
				}
			}
		}
		cout<<ans<<endl;
	}
}

C++: #include<iostream>

using namespace std;

const int maxWH = 52;
int H, W;
int C[maxWH][maxWH] = {0};

void dfs(int hh, int ww) {
  int dh[] = {-1, 0, 1, 0, -1, -1, 1, 1};
  int dw[] = {0, -1, 0, 1, -1, 1, -1, 1};
  //cout<<hh<<" "<<ww<<endl;
  if(0<=hh && 0<=ww && hh<H && ww<W) {
    if(C[hh][ww] == 1) {
      C[hh][ww] = 0; // false
      /*
      cout<<"now "<<hh<<" "<<ww<<endl;
      for(int i=0; i<8; i++) {
        cout<<hh+dh[i]<<" "<<ww+dw[i]<<endl;
      }
      */
      for(int i=0; i<8; i++) {
        dfs(hh+dh[i], ww+dw[i]);
      }
    }
  }
}

int main() {
  while(cin>>W>>H && !(W==0 && H==0)) {
    for(int i=0; i<H; i++) {
      for(int j=0; j<W; j++) {
	cin>>C[i][j];
      }
    }

    /*
    cout<<endl;
    for(int i=0; i<H; i++) {
      for(int j=0; j<W; j++) {
	cout<<C[i][j]<<" ";
      }
      cout<<endl;
    }
    */
    
    int ans = 0;
    for(int i=0; i<H; i++) {
      for(int j=0; j<W; j++) {
	if(C[i][j] == 1) {
	  ans++;
	  dfs(i,j);
	}
      }
    }
    cout<<ans<<endl;
  }
}