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++: //
//  main.cpp
//  AOJ-1160
//
//  Created by Kenta Kodera on 2017/06/18.
//  Copyright ?? 2017??´ Kenta Kodera. All rights reserved.
//

#include <iostream>
#include <stdio.h>
#include <algorithm>
#include <vector>
#include <queue>
#include <numeric>
#include <string>
#include <string.h>
#include <map>
#include <set>
#include <functional>
#include <complex>
#include <stack>
#include <tuple>
#include <array>
#include <ctype.h> // isdigit
#include <cassert>
using namespace std;

int W, H;

void dfs(vector<vector<int>> &field, int h, int w){
  int dhw[3] = {1, -1, 0};
  field[h][w] = 0;
  
  for(int i=0; i<3; i++){
    for(int j=0; j<3; j++){
      int nh = h+dhw[i];
      int nw = w+dhw[j];
      for(int h=0; h<H; h++){
        for(int w=0; w<W; w++){
          if(0<=nh && nh<H && 0<=nw && nw<W && field[nh][nw]==1){
            dfs(field, nh, nw);
          }
        }
      }
    }
  }
  
}


int main(){
  
  while(cin >> W >> H, W|H){
    vector<vector<int>> field(H);
    for(int h=0; h<H; h++){
      field[h].resize(W);
    }
    
    for(int h=0; h<H; h++){
      for(int w=0; w<W; w++){
        cin >> field[h][w];
      }
    }
    
    int n=0;
    for(int h=0; h<H; h++){
      for(int w=0; w<W; w++){
        if(field[h][w] == 1){
          dfs(field, h, w);
          n++;
        }
      }
    }
    cout << n << endl;
    
  }
  

  return 0;
}

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

int w, h;
int c[50][50];
int dx[8] = {1, 1, 1, 0, -1, -1, -1, 0};
int dy[8] = {1, 0, -1, -1, -1, 0, 1, 1};

int dfs(int x, int y) {
  if (x < 0 || y < 0 || x >= w || y >= h) return 0;
  if (c[y][x] == 0) return 0;
  c[y][x] = 0;
  for (int i = 0; i < 8; i++) dfs(x + dx[i], y + dy[i]);
  return 1;
}

int main() {
  while (1) {
    scanf("%d%d", &w, &h);
    if (w == 0) break;
    for (int i = 0; i < h; i++)
      for (int j = 0; j < w; j++) scanf("%d", &c[i][j]);
    int counter = 0;
    for (int i = 0; i < h; i++)
      for (int j = 0; j < w; j++) counter += dfs(j, i);
    printf("%d\n", counter);
  }
}

C++: //
// Created by elegant-belltree on 15/06/03.
//

#include <iostream>
#include <set>

using namespace std;

int main(){
    int w,h;
    int c[50][50];

    while (cin>>w>>h && (w>0 || h>0)) {
        int label=2;
        set<int> labels;

        for (int n = 0; n < 2; ++n) {
            for (int i = 0; i < h; ++i) {
                for (int j = 0; j < w; ++j) {
                    if(n==0) {
                        cin >> c[j][i];
                    }
                    if (0<c[j][i]) {
                        for (int k = -1; k < n+1 && i+k<h; ++k) {
                            for (int l = -1; (n!=0 || k!=0 || l!=0) && l < 3 && j + l < w; ++l) {
                                if (-1 < i + k && -1 < j + l && 0 < c[j + l][i + k] && (c[j][i] == 1 || c[j + l][i + k] < c[j][i])) {
                                    if(n==1){
                                        labels.erase(c[j][i]);
                                    }
                                    c[j][i] = c[j + l][i + k];
                                }
                            }
                        }
                        if (c[j][i] == 1) {
                            c[j][i] = label++;
                            labels.insert(c[j][i]);
                        }
                    }
                }
            }
        }
        /*for (int m = 0; m < h; ++m) {
            for (int i = 0; i < w; ++i) {
                cout<<c[i][m]<<" ";
            }
            cout<<endl;
        }*/
        cout<<labels.size()<<endl;
    }
    return 0;
}

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

void update(int x,int y,vector< vector<int> >& map){
	if(map[y][x]==1){
		map[y][x]=2;
	}else{
		return;
	}
	if(x!=0)update(x-1,y,map);
	if(y!=0)update(x,y-1,map);
	if(x!=0&&y!=0)update(x-1,y-1,map);
	if(y!=map.size()-1)update(x,y+1,map);
	if(x!=map[0].size()-1)update(x+1,y,map);
	if(y!=map.size()-1&&x!=0)update(x-1,y+1,map);
	if(y!=map.size()-1&&x!=map[0].size()-1)update(x+1,y+1,map);
	if(x!=map[0].size()-1&&y!=0)update(x+1,y-1,map);
}
int main(){
	while(true){
		vector< vector<int> > map;
		int w,h,tmp,sum=0;
		cin>>w>>h;
		if(w==0)break;
		map.resize(h);
		for(int y=0;y<h;y++){
			for(int x=0;x<w;x++){
				map[y].resize(w);
				cin>>tmp;
				map[y][x]=tmp;
			}
		}
		for(int y=0;y<h;y++){
			for(int x=0;x<w;x++){
				if(map[y][x]==1){
					sum++;
					update(x,y,map);
				}
			}
		}
		cout<<sum<<endl;
	}
	return 0;
}