Go: ///
// File:  1160.go
// Author: ymiyamoto
//
// Created on Sun Mar  4 20:45:57 2018
//
package main

import (
	"fmt"
)

var w, h int
var graph [][]string

func dfs(visited [][]bool, x, y int) {
	visited[x][y] = true

	for i := -1; i <= 1; i++ {
		for j := -1; j <= 1; j++ {
			dx := x + i
			dy := y + j
			if 0 <= dx && dx < h && 0 <= dy && dy < w && graph[dx][dy] == "1" && !visited[dx][dy] {
				dfs(visited, dx, dy)
			}
		}
	}
}

func main() {
	for {
		fmt.Scan(&w, &h)
		if w == 0 && h == 0 {
			break
		}

		graph = make([][]string, h)
		for i := range graph {
			graph[i] = make([]string, w)
		}

		for i := 0; i < h; i++ {
			for j := 0; j < w; j++ {
				var s string
				fmt.Scan(&s)
				graph[i][j] = s
			}
		}

		visited := make([][]bool, h)
		for i := range visited {
			visited[i] = make([]bool, w)
		}

		count := 0
		for i := range graph {
			for j := range graph[i] {
				if graph[i][j] == "1" && !visited[i][j] {
					dfs(visited, i, j)
					count++
				}
			}
		}

		fmt.Println(count)
	}
}

C++: #include<iostream>
using namespace std;
#define MAX (256)

int field[MAX][MAX];
int ans = 0;

void dfs(int i, int j){
	for(int k = -1; k <= 1; k++){
		for(int l = -1; l <= 1; l++){
			if(field[i+k][j+l] == 1){
				field[i+k][j+l] = 0;
				dfs(i+k, j+l);
			}
		}
	}
}

int main(){
	int k, l;

	while(1){
		ans = 0;
		cin >> l >> k;

		if((k|l) == 0) break;

		for(int i=0; i < MAX; i++){
			for(int j=0; j < MAX; j++) field[i][j]= 0;
		}

		for(int i=0; i < k; i++){
				for(int j=0; j < l; j++){
					cin >> field[i][j];
			}
		}

		for(int i=0; i < k; i++){
			for(int j=0; j < l; j++){
				if(field[i][j] == 1){
					field[i][j] = 0;
					dfs(i, j);
					ans++;
				}
			}
		}
		
		cout << ans << endl;
	}
}

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

using namespace std;
using ll = long long;
using ld = long double;
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define reps(i,s,n) for(int i=(int)(s);i<(int)(n);i++)
	int w, h;
	int c[50][50] = {};

	void dfs(int i, int j) {
		c[i][j] = 0;

		for (int di = -1; di <= 1;di++) {
			for (int dj = -1; dj <= 1;dj++) {
				int ni = i + di;
				int nj = j + dj;

				if (0 <= ni&&ni < h && 0 <= nj&&nj < w && c[ni][nj] == 1) {
					dfs(ni, nj); 
				}
			}
		}
		return;
}

int main() {
	cin.sync_with_stdio(false);
	vector<int>ans;
	while (1) {
		cin >> w >> h;
		rep(i, h) {
			rep(j, w) {
				cin >> c[i][j];
			}
		}
		int res = 0;
		rep(i, h) {
			rep(j, w) {
				if (c[i][j] == 1) {
					dfs(i, j);
					res++;
				}
			}
		}
		ans.push_back(res);

		if (w == 0&&h == 0) {
			break;
		}
	}
	rep(i, ans.size()) {
		cout << ans[i] << endl;
	}

	return 0;
}

C++: #include "bits/stdc++.h"
#define REP(i, n, N) for(ll i=(n); i < N; i++)
#define CK(N, A, B) (A <= N && N < B)
#define p(s) cout << (s) << endl
#define p2(a, b) cout << (a) << ' ' << (b) << endl
using namespace std;
typedef long long ll;

const int NODE_SIZE=10101;
int H;
int W;
int start_y, start_x;
int island_num=2;

int field[NODE_SIZE][NODE_SIZE];

int d[NODE_SIZE][NODE_SIZE];

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

void bfs(){
    queue<pair<int,int>> q;
    bool visited[H][W];
    REP(i,0,H) REP(j,0,W) visited[i][j]=false;
    REP(i,0,H) REP(j,0,W) d[i][j]=-1;
    q.push({start_y, start_x});
    d[start_y][start_x]=0;
    while(!q.empty()){
        int cur_y = q.front().first;
        int cur_x = q.front().second;
        int curStep = d[cur_y][cur_x];
        q.pop();
        if(visited[cur_y][cur_x]) continue;
        visited[cur_y][cur_x] = true;
        field[start_y][start_x]=island_num;

        REP(k,0,8){
            int next_y = cur_y + dy[k];
            int next_x = cur_x + dx[k];

            if(!CK(next_y,0,H) || !CK(next_x,0,W))continue;
            if(field[next_y][next_x]==1){
                field[next_y][next_x]=island_num;
            }else{
                continue;
            }
            if(!visited[next_y][next_x]){
                q.push({next_y, next_x});
                d[next_y][next_x] = d[cur_y][cur_x] + 1;
            }
        }
    }
}

int main() {
    while (cin >> W >> H && W){
        island_num = 2;
        REP(i,0,H){
            REP(j,0,W){
                cin >> field[i][j];
            }
        }
        REP(i,0,H){
            REP(j,0,W){
                if(field[i][j]==1){
                    start_y=i,start_x=j;
                    bfs();
                    island_num++;
                }
            }
        }
        p(island_num-2);
    }

    return 0;
}

C++: #include <iostream>
using namespace	std;
int h,w,c[50][50];
void dfs(int y,int x){
  c[y][x]=0;
  for(int i=-1;i<=1;i++)
    for(int j=-1;j<=1;j++)
      if(0<=y+i&&y+i<h&&0<=x+j&&x+j<w)
        if(c[y+i][x+j]) dfs(y+i,x+j);
}

int main(){

  for(;cin>>w>>h,w;){
    int r=0;
    for(int i=0;i<h;i++) for(int j=0;j<w;j++) cin>>c[i][j];
    for(int i=0;i<h;i++) for(int j=0;j<w;j++){
        if(c[i][j]){
          r++;
          dfs(i,j);
        }
      }
    cout<<r<<endl;
  }
  return 0;

}

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

void search(int y, int x, int h, int w, int** field) {
    field[y][x] = 0;
    for (int ny = y - 1; ny <= y + 1; ny++) {
        for (int nx = x - 1; nx <= x + 1; nx++) {
            if (0 <= ny && ny < h && 0 <= nx && nx < w && field[ny][nx] == 1) {
                search(ny, nx, h, w, field);
            }
        }
    }
}

int main() {
    while (true) {
        int w, h;
        cin >> w >> h;
        if ((w | h) == 0) {
            break;
        }
        int** field = new int* [h];
        for (int i = 0; i < h; i++) {
            field[i] = new int [w];
        }
        for (int y = 0; y < h; y++) {
            for (int x = 0; x < w; x++) {
                cin >> field[y][x];
            }
        }
        int count = 0;
        for (int y = 0; y < h; y++) {
            for (int x = 0; x < w; x++) {
                if (field[y][x] == 1) {
                    search(y, x, h, w, field);
                    count++;
                }
            }
        }
        cout << count << endl;
        for (int i = 0; i < h; i++) {
            delete[] field[i];
        }
        delete[] field;
    }
}

C++: #include<iostream>
#include<queue>
using namespace std;
int dx[] = {1,1,0,-1,-1,-1,0,1};
int dy[] = {0,1,1,1,0,-1,-1,-1};
int c[51][51];
int main()
{

	int w, h;

	while (cin >> w && cin >> h && w != 0 && h != 0)
	{
		for (int i = 1; i < h + 1; i++)
		{
			for (int j = 1; j < w + 1; j++)
			{
				int tmp;
				cin >> tmp;
				if (tmp == 0)
				{
					c[i][j] = -1;
				}
				else
				{
					c[i][j] = 0;
				}
			}
		}

		int count = 0;
		queue<pair<int,int>> q;
		for (int i = 1; i < h + 1; i++)
		{
			for (int j = 1; j < w + 1; j++)
			{
				if (c[i][j] != 0)continue;
				q.push(make_pair(i,j));
				c[i][j] = 1;
				while (q.size() > 0)
				{
					pair<int, int> p = q.front();
					q.pop();
					int y = p.first;
					int x = p.second;

					for (int d = 0; d < 8; d++)
					{
						int nx = x + dx[d];
						int ny = y + dy[d];

						if (nx < 1 || ny < 1 || nx > w || ny > h)continue;
						if (c[ny][nx] != 0)continue;
						q.push(make_pair(ny, nx));
						c[ny][nx] = 1;
					}
				}
				count++;
			}
		}

		cout << count << endl;


	}

	return 0;
}