Go: package main

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

var sc = bufio.NewScanner(os.Stdin)
var route [][]int

func scanInt() int {
	num, _ := strconv.Atoi(scanString())
	return num
}

func scanString() string {
	sc.Scan()
	return sc.Text()
}

func init() {
	sc.Split(bufio.ScanWords)
}

func dfs(h, w int) {
	if route[h][w] == 0 {
		return
	}

	route[h][w] = 0
	for _, x := range []int{-1, 0, 1} {
		for _, y := range []int{-1, 0, 1} {
			if route[h+x][w+y] == 0 {
				continue
			}
			dfs(h+x, w+y)
		}
	}
}

func main() {
	writer := bufio.NewWriter(os.Stdout)
	for {
		w, h := scanInt(), scanInt()
		if w == 0 && h == 0 {
			break
		}

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

		total := 0
		for i := 1; i <= h; i++ {
			for j := 1; j <= w; j++ {
				if route[i][j] == 1 {
					total++
					dfs(i, j)
				}
			}
		}
		fmt.Fprintln(writer, total)
	}
	writer.Flush()
}

C++: #include <cstdio>
#include <cstring>

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

int dfs(int sx, int sy) {
    if(sx<0 || sx>w-1 || sy<0 || sy>h-1) return 0;
    if(map[sy][sx] == '0') return 0;

    map[sy][sx] = '0';

    dfs(sx+1,sy);
    dfs(sx,sy+1);
    dfs(sx-1,sy);
    dfs(sx,sy-1);
    dfs(sx+1,sy+1);
    dfs(sx+1,sy-1);
    dfs(sx-1,sy+1);
    dfs(sx-1,sy-1);
    return 1;
}

int main(void)
{
    int px,py;

    while(true)
    {
        res = 0;
        scanf("%d%d", &w, &h);
        if(!w && !h) break;
        for(int j=0; j < h; j++)
        for(int i=0; i < w; i++)
            scanf("%s", &map[j][i]);

        for(int j=0; j < h; j++)
        for(int i=0; i < w; i++)
            res += dfs(i, j);

        printf("%d\n", res);
    }

    return 0;
}

C++: #include <map>
#include <set>
#include <list>
#include <cmath>
#include <queue>
#include <stack>
#include <cstdio>
#include <string>
#include <vector>
#include <complex>
#include <cstdlib>
#include <cstring>
#include <numeric>
#include <sstream>
#include <iostream>
#include <algorithm>
#include <functional>
  
#define mp       make_pair
#define pb       push_back
#define all(x)   (x).begin(),(x).end()
#define rep(i,n) for(int i=0;i<(n);i++)
  
using namespace std;
  
typedef    long long          ll;
typedef    unsigned long long ull;
typedef    vector<bool>       vb;
typedef    vector<int>        vi;
typedef    vector<vb>         vvb;
typedef    vector<vi>         vvi;
typedef    pair<int,int>      pii;
  
const int INF=1<<29;
const double EPS=1e-9;
  
const int dx[]={1,0,-1,0,1,1,-1,-1},dy[]={0,-1,0,1,1,-1,-1,1};

bool ok(std::vector<vector<int> > &map, int x, int y) {
    int H = map.size();
    int W = map[0].size();
    if (x < 0 || x >= W || y < 0 || y >= H) return false;
    return true;
}

void color(std::vector<vector<int> > &map, int i, int j) {
    if (map[i][j] == -1) return;
    map[i][j] = -1;

    for (int k = 0; k < 8; k++) {
        int px = j + dx[k];
        int py = i + dy[k];
        if (!ok(map, px, py)) continue;
        if (map[py][px] == 0) continue;
        if (map[py][px] == 1) {
            color(map, py, px);
        }
    }
}

int main(int argc, char const *argv[]) {
    int W, H;
    while(cin >> W >> H) {
        if (W == 0 && H == 0) break;
        std::vector<vector<int> > map(H, vector<int>(W, 0));
        for (int i = 0; i < H; i++) {
            for (int j = 0; j < W; j++) {
                cin >> map[i][j];
            }
        }
        int count = 0;
        for (int i = 0; i < H; i++) {
            for (int j = 0; j < W; j++) {
                if (map[i][j] == 1) {
                    count++;
                    color(map, i, j);
                }
            }
        }
        cout << count << endl;
    }
    return 0;
}

C++: #include <iostream>
#include <stack>
#include <utility>

using namespace std;

typedef pair<int, int> pii;

int field[52][52];

int main(){
	while(true){
		int w, h;
		cin >> w >> h;
		if(w == 0 && h == 0){ break; }
		for(int x = 0; x <= w + 1; ++x){ field[0][x] = field[h + 1][x] = 0; }
		for(int y = 1; y <= h; ++y){
			field[y][0] = field[y][w + 1] = 0;
			for(int x = 1; x <= w; ++x){ cin >> field[y][x]; }
		}
		int answer = 0;
		for(int y = 1; y <= h; ++y){
			for(int x = 1; x <= w; ++x){
				if(field[y][x] == 0){ continue; }
				++answer;
				std::stack<pii> stk;
				stk.push(pii(x, y));
				while(!stk.empty()){
					pii pt = stk.top();
					stk.pop();
					if(field[pt.second][pt.first] > 0){
						field[pt.second][pt.first] = 0;
						stk.push(pii(pt.first - 1, pt.second - 1));
						stk.push(pii(pt.first - 1, pt.second));
						stk.push(pii(pt.first - 1, pt.second + 1));
						stk.push(pii(pt.first, pt.second - 1));
						stk.push(pii(pt.first, pt.second + 1));
						stk.push(pii(pt.first + 1, pt.second - 1));
						stk.push(pii(pt.first + 1, pt.second));
						stk.push(pii(pt.first + 1, pt.second + 1));
					}
				}
			}
		}
		cout << answer << endl;
	}
	return 0;
}

C++: // 2013/07/05 Tazoe

#include <iostream>
using namespace std;

void DFS(int M[52][52], int y, int x)
{
	M[y][x] = 0;

	if(M[y-1][x]==1)
		DFS(M, y-1, x);
	if(M[y-1][x+1]==1)
		DFS(M, y-1, x+1);
	if(M[y][x+1]==1)
		DFS(M, y, x+1);
	if(M[y+1][x+1]==1)
		DFS(M, y+1, x+1);
	if(M[y+1][x]==1)
		DFS(M, y+1, x);
	if(M[y+1][x-1]==1)
		DFS(M, y+1, x-1);
	if(M[y][x-1]==1)
		DFS(M, y, x-1);
	if(M[y-1][x-1]==1)
		DFS(M, y-1, x-1);
}

int main()
{
	while(true){
		int w, h;
		cin >> w >> h;

		if(w==0 && h==0)
			break;

		int M[52][52];
		for(int y=0; y<h+2; y++){
			for(int x=0; x<w+2; x++){
				M[y][x] = 0;
			}
		}

		for(int y=1; y<=h; y++){
			for(int x=1; x<=w; x++){
				cin >> M[y][x];
			}
		}

		int cnt = 0;

		for(int y=1; y<=h; y++){
			for(int x=1; x<=w; x++){
				if(M[y][x]==1){
					cnt++;
					DFS(M, y, x);
				}
			}
		}

		cout << cnt << endl;
	}

	return 0;
}

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

int main(){
    do{
        long long w, h;
        cin >> w >> h;
        if(w == 0)break;
        
        vector<vector<int>> c(h + 2, vector<int>(w + 2));
        for(int i = 0; i < h; ++i){
            for(int j = 0; j < w; ++j){
                cin >> c[i + 1][j + 1];
            }
        }
        
        queue<pair<int, int>> q;
        constexpr int move[9] = {0, 1, 1, -1, 0, -1, -1, 1};
        
        long long ans = 0;
        
        for(int i = 1; i <= h; ++i){
            for(int j = 1; j <= w; ++j){
                if(c[i][j]){
                    ++ans;
                    
                    q.emplace(i, j);
                    c[i][j] = false;
                    
                    while(!q.empty()){
                        auto t = q.front();
                        q.pop();
                        for(int i = 0; i < 8; ++i){
                            int y = t.first + move[i];
                            int x = t.second + move[i + 1];
                            if(c[y][x]){
                                q.emplace(y, x);
                                c[y][x] = false;
                            }
                        }
                    }
                    
                }
            }
        }
        
        cout << ans << endl;
        
    }while(true);
    
    return 0;
}