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++: // テ・ツ淞コテヲツ慊ャテ」ツδ?」ツδウテ」ツδ療」ツδャテ」ツδシテ」ツδ?(テァツクツョテ・ツーツ湘ァツ可?

#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,n) for(int (i)=(a); (i)<(n); (i)++)
#define repq(i,a,n) for(int (i)=(a); (i)<=(n); (i)++)
#define repr(i,a,n) for(int (i)=(a); (i)>=(n); (i)--)
#define int long long
template<typename T> void chmax(T &a, T b) {a = max(a, b);}
template<typename T> void chmin(T &a, T b) {a = min(a, b);}
template<typename T> void chadd(T &a, T b) {a = a + b;}
typedef pair<int, int> pii;
typedef long long ll;
constexpr ll INF = 1001001001001001LL;
constexpr ll MOD = 1000000007LL;

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

int W, H;
int board[60][60];
bool used[60][60];

signed main() {
    while(cin >> W >> H, W || H) {
        memset(used, false, sizeof(used));
        rep(i,0,H) rep(j,0,W) cin >> board[i][j];

        int ans = 0;
        rep(i,0,H) rep(j,0,W) {
            if(used[i][j] || board[i][j] == 0) continue;
            ans++; used[i][j] = true;

            queue<pii> q;
            q.push(pii(i, j));

            while(!q.empty()) {
                pii t = q.front(); q.pop();
                int x = t.first, y = t.second;
                rep(k,0,8) {
                    int nx = x + dx[k], ny = y + dy[k];
                    if(nx < 0 || nx >= H || ny < 0 || ny >= W) continue;
                    if(used[nx][ny] || board[nx][ny] == 0) continue;
                    used[nx][ny] = true;
                    q.push(pii(nx, ny));
                }
            }
        }
        cout << ans << endl;
    }
    return 0;
}

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

using namespace std;

#define llong long long 
int w,h;
int sum;
int area[50][50];
int nw[8] = {0, 1, 1, 1, 0, -1, -1, -1};
int nh[8] = {1, 1, 0, -1, -1, -1, 0, 1};

void solve(int h, int w){
	if(area[h][w] == 0)return;
	area[h][w] == 0;
	for(int i = 0; i < 8; i++){
		int sh = h + nh[i];
		int sw = w + nw[i];
		if(sh < 0 || sw < 0 || sh >= h || sw >= w) continue;
		solve(sh, sw);
	}
	return;
}

int main(){

	while(cin >> w >> h, w){
		sum = 0;
		fill_n(*area, 50 * 50, 0);
		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){
					sum++;
					solve(i, j);
				}
			}
		}

		cout << sum << endl;
}
	return 0;
}

C++: #include<iostream>
#include<cstdio>
#include<algorithm>
using namespace std;
int island[50][50];
void func(int,int);

int main(){
  int w,h;
  int ans;
  
  while(1){
    cin>>w>>h;
    if(w==0 && h==0) break;
    ans=0;
    
    for(int i=0;i<h;i++){
      for(int l=0;l<w;l++){
        cin>>island[i][l];
      }
    }
    
    for(int i=0;i<h;i++){
      for(int l=0;l<w;l++){
        if(island[i][l]==1){
          func(i,l);
          ans++;
        }
      }
    }
    printf("%d\n",ans);
  }
  return 0;
}

void func(int x,int y){
  island[x][y]=0;
  for(int i=x-1;i<x+2;i++){
    for(int l=y-1;l<y+2;l++){
      if(island[i][l]==1)
        func(i,l);
    }
  }
}

C++: #include <iostream>

using namespace std;

int W,H;

bool table[50][50];


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

void dfs(int x,int y){
	table[x][y]=0;
	for(int i=0;i<8;i++){
		if(0<=x+dx[i]&&x+dx[i]<W&&0<=y+dy[i]&&y+dy[i]<H&&table[x+dx[i]][y+dy[i]])
			dfs(x+dx[i],y+dy[i]);
	}
	return ;
}


int main(void){
	while(cin >> W >> H,W|H){
		for(int y=0;y<H;y++)
			for(int x=0;x<W;x++)
				cin >> table[x][y];
		int num=0;
		for(int y=0;y<H;y++)
			for(int x=0;x<W;x++)
				if(table[x][y])
					num++,dfs(x,y);
		cout << num << endl;
	}
	return 0;
}

C++: #include<stdio.h>
#include<iostream>

int field[51][51];
int w,h;

void land(int x,int y){
	field[x][y]=0;

	for(int yy=-1;yy<=1;yy++){
		for(int xx=-1;xx<=1;xx++){
			if(x+xx>=0&&x+xx<=w&&y+yy>=0&&y+yy<=h){
			   if(field[x+xx][y+yy]==1) land(x+xx,y+yy);
			}
		}
	}
	return;
}

int main(void){

	int kazu=0;

	scanf("%d %d",&w,&h);

	if(w==0||h==0) return 0;

	for(int i=0;i<h;i++){
		for(int j=0;j<w;j++){
			scanf("%d",&field[j][i]);
		}
	}

	for(int i=0;i<h;i++){
		for(int j=0;j<w;j++){

			if(field[j][i]==1){
				land(j,i);
				kazu++;
			}

		}
	}

	printf("%d",kazu);
	return 0;
}

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

using namespace std;

int ans = 0;
bool dfs(vector< vector<int> > &island,int x,int y){
	int dx[8] = {-1,-1,-1, 0, 0, 1, 1, 1};
	int dy[8] = {-1, 0, 1,-1, 1,-1, 0, 1};
	if (island[x][y] == 0) return false;
	island[x][y] = 0;
	for (int i = 0; i< 8; i++){
		if(0 <= x + dx[i] and x + dx[i] < island.size() and 0 <= y + dy[i] and y + dy[i] < island[0].size()){
			dfs(island,x + dx[i],y + dy[i]);
		}
	}
	return true;
}

int main(){
	while(1){
		int w,h; cin >> w >> h;
		int ans = 0;
		if (w + h == 0) break;
		vector< vector<int> > island(h, vector<int>(w,0));
		for (int i = 0; i < h; i++){
			for (int j = 0; j < w; j++){
				cin >> island[i][j];
			}
		}

		for (int i = 0; i < h; i++){
			for (int j = 0; j < w; j++){
				if (dfs(island,i,j)){
					ans++;
				}
			}
		}
		cout << ans << endl;
	}
return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
using ll=long long;
typedef pair<int,int> P;
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
int w,h;
int nx,ny;
vector<vector<int>> G;
void dfs(int a,int b){
     if(0>a|| a>=h || 0>b|| b>=w) return ;
     if( G.at(a).at(b)==0) return ; 
     G.at(a).at(b)=0;
    for(int k=-1;k<=1;k++){
        for(int s=-1;s<=1;s++){
            nx=a+k;
            ny=b+s;
            dfs(nx,ny);
        }
    }
}
 
 
 
int main(){
    cin>>w>>h;
    G.resize(h,vector<int>(w));
    for(int i=0;i<h;i++){
        for(int j=0;j<w;j++){
            cin>>G.at(i).at(j);
        }
    }
    int count=0;
    for(int i=0;i<h;i++){
        for(int j=0;j<w;j++){
            if(G.at(i).at(j)==1){
                count++;
                dfs(i,j);
            }
        }
    }
cout<<count<<endl;
}