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>
#include<cstdio>
using namespace std;
int mas[100][100];
int dx[8]={1,1,0,-1,-1,-1,0,1},dy[8]={0,1,1,1,0,-1,-1,-1};
int sx,sy,gx,gy,w,h,cnt=0;
void dfs(int x,int y);
int main(){
  while(1){
    cnt=0;
  cin >> w >> h;
  if(w==0 && h==0) break;
  for(int i=0;i<h;i++){
    for(int j=0;j<w;j++){
      cin >> mas[i][j];
    }
  }
  for(int i=0;i<h;i++){
    for(int j=0;j<w;j++){
      if(mas[i][j]==1){
        cnt++;
        dfs(j,i);
      }
    }
  }
  cout << cnt << endl;
  }
}
void dfs(int x,int y){
  mas[y][x]=0;
  for(int i=0;i<8;i++){
    int nx=x+dx[i];
    int ny=y+dy[i];
    if(nx >= 0&& nx < w && ny >= 0 && ny < h && mas[ny][nx]==1){
        dfs(nx,ny);
      }
  }
}

C++: #include<iostream>
#include<cstring>
#include<string>
#include<algorithm>
#include<cmath>
#include<vector>
using namespace std;
typedef long long ll;
#define rep(i,s,n) for(int i = s;i<n;i++)
#define repe(i,s,n) for(int i = s;i<=n;i++)
static const ll maxLL = (ll)1 << 62;

//dfs(bool型)
int dy[]={-1,0,1,0,1,-1,-1,1};
int dx[]={0,1,0,-1,1,1,-1,-1};
bool visited[1000][1000];
int t[1000][1000];
char copy_t[1000][1000];
int h,w;
int si,sj;

void dfs(int y,int x){
  if(y<=0||x<=0)return;
  if(y>h||x>w)return;
  if(t[y][x]==0)return;
  if(visited[y][x])return;
  visited[y][x]=true;
  for(int i=0;i<8;i++){
    int ny=y+dy[i];
    int nx=x+dx[i];
    dfs(ny,nx);
  }
  return;
}

int main(){
    int cnt=0;
    cin>>w>>h;
    repe(i,1,h){
        for(int j=1;j<=w;j++){
            cin>>t[i][j];
        }
    }
    repe(i,1,h){
        repe(j,1,w){
             if(t[i][j]==1 && visited[i][j]==false)cnt++;
        dfs(i,j);
        }
    }
    cout<<cnt<<endl;
    return 0;
}

C++: #include<cstdio>
using namespace std;
void func(int,int);
int a,b;
int sima[51][51];
int cnt;
int y,x;
int main(void)
{
	int i,j;
	scanf("%d",&a);
	scanf("%d",&b);
	while(!(a==0 && b==0)){
		
		for(i=0;i<b;i++){
			for(j=0;j<a;j++){
				scanf("%d",&sima[i][j]);
			}
		}
		cnt=0;
		for(i=0;i<b;i++){
			for(j=0;j<a;j++){
				if(sima[i][j]==1){
					func(i,j);
					cnt++;
				}
			}
		}
		printf("%d\n",cnt);
		scanf("%d",&a);
		scanf("%d",&b);
	}
	return 0;
}
void func(int y,int x)
{
	if(y-1>=0){
		if(sima[y-1][x]==1){
			sima[y-1][x]=0;
			func(y-1,x);
		}
	}
	if(x-1>=0){
		if(sima[y][x-1]==1){
			sima[y][x-1]=0;
			func(y,x-1);	
		}
	}
	if(y+1<=a){
		if(sima[y+1][x]==1){
			sima[y+1][x]=0;
			func(y+1,x);
		}
	}
	if(x+1<=b){
		if(sima[y][x+1]==1){
			sima[y][x+1]=0;
			func(y,x+1);
		}
	}
	if(y-1>=0 && x+1<=b){
		if(sima[y-1][x+1]==1){
			sima[y-1][x+1]=0;
			func(y-1,x+1);
		}
	}
	if(y-1>=0 && x-1>=0){
		if(sima[y-1][x-1]==1){
			sima[y-1][x-1]=0;
			func(y-1,x-1);
		}
	}
	if(y+1<=a && x+1<=b){
		if(sima[y+1][x+1]==1){
			sima[y+1][x+1]=0;
			func(y+1,x+1);
		}
	}
	if(y+1<=a && x-1>=0){
		if(sima[y+1][x-1]==1){
			sima[y+1][x-1]=0;
			func(y+1,x-1);
		}
	}
}

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

int dx[8]={0,1,1,1,0,-1,-1,-1};
int dy[8]={1,1,0,-1,-1,-1,0,1};
int d[55][55];

void init(){
  for(int i=0;i<55;i++)for(int j=0;j<55;j++)d[i][j]=0;
}

void Delete(int sx,int sy,int h,int w){
  queue<int>que;
  que.push(sx);que.push(sy);
  while(que.size()){
    int x=que.front();que.pop();
    int y=que.front();que.pop();
    for(int i=0;i<8;i++){
      if(d[y+dy[i]][x+dx[i]]==1&&0<=y+dy[i]&&y+dy[i]<h&&0<=x+dx[i]&&x+dx[i]<w){
	d[y+dy[i]][x+dx[i]]=0;
	que.push(x+dx[i]);
	que.push(y+dy[i]);
      }
    }
  }
}

int solve(int w,int h){
  int cnt=0;
  for(int i=0;i<h;i++){
    for(int j=0;j<w;j++){
      if(d[i][j]==1){
	Delete(j,i,h,w);
	cnt++;
      }
    }
  }
  return cnt;
}

int main(){
  int w,h;
  while(1){
    cin>>w>>h;
    if(w==0&&h==0)break;
    init();
    for(int i=0;i<h;i++)for(int j=0;j<w;j++)cin>>d[i][j];
    cout<<solve(w,h)<<endl;
  }
}

C++: #include <iostream>
#include <vector>

using namespace std;

#define vec vector
#define rep(i, n) for (int i = 0; i < (int)n; i++)

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

int dp[55][55];
int c[55][55];

int check(int x, int y)
{
	if (dp[x][y]) return 0;
	if (c[x][y] == 0) return 0;
	dp[x][y] = 1;
	
	rep(i, 8) {
		int xx = x + dx[i];
		int yy = y + dy[i];
		int take = check(xx, yy);
	}
	return 1;
}

int main(void)
{
	while(1) {
		int w, h;
		cin >> w >> h;
		if (w == 0) break;
		rep(i, 55) rep(j, 55) c[i + 1][j + 1] = 0;
		rep(i, h) rep (j, w) cin >> c[i + 1][j + 1];
		rep(i, 55) rep(j, 55) dp[i][j] = 0;
		rep(i, 55) {
			dp[0][i] = 1;
			dp[i][0] = 1;
			dp[h + 1][i] = 1;
			dp[i][w + 1] = 1;
		}

		int ans = 0;
		rep(i, h) rep(j, w) if (c[i + 1][j + 1]) ans += check(i + 1, j + 1);
		cout << ans << endl;
	}
	return 0;
}

C++: #include <iostream>
#include <vector>
using namespace std;
int ans;
int w, h;
//?§???????
const int mx[] = {-1, 0, 1, -1, 1, -1, 0, 1 };
const int my[] = { 1, 1, 1, 0, 0, -1, -1, -1};
vector<int> vx;
vector<int> vy;

vector<vector<int>> area;
int islands = 0;

//????±????????????¨????????¢?´¢
void dfs(int i,int j){
	for (int n = 0; n < vx.size(); n++){
		int x = j + vx[n];
		int y = i + vy[n];
		if (x >= 0 && x < w &&
			y >= 0 && y < h &&
			area[y][x] == 1){
			area[y][x] = 2;
			dfs(y,x);
		}
	}
}

int main(){
	for (int i = 0; i < 8; i++){
		vx.push_back(mx[i]);
		vy.push_back(my[i]);
	}
	while (1){
		cin >> w >> h;
		if (w == 0 && h == 0) break;
		//?????????
		islands = 0;
		area.clear();
		area = vector<vector<int>>(h, vector<int>(w));
		//??\???
		for (int i = 0; i < h; i++){
			for (int j = 0; j < w; j++){
				cin >> area[i][j];
			}
		}
		//??¨??¢?´¢
		for (int i = 0; i < h; i++){
			for (int j = 0; j < w; j++){
				if (area[i][j] == 1){
					islands++;
					area[i][j] = 2;
					dfs(i, j);
				}
			}
		}
		cout << islands << endl;
	}
	return 0;
}