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 <stdio.h>
#include <iostream>

using namespace std;

int c[51][51];

void deep(int i,int n){
  if(c[i][n+1]==1){
    c[i][n+1]=2;
    deep(i,n+1);
  }
  if(c[i+1][n]==1){
    c[i+1][n]=2;
    deep(i+1,n);
  }
  if(c[i][n-1]==1){
    c[i][n-1]=2;
    deep(i,n-1);
  }
  if(c[i-1][n]==1){
    c[i-1][n]=2;
    deep(i-1,n);
  }
  if(c[i+1][n+1]==1){
    c[i+1][n+1]=2;
    deep(i+1,n+1);
  }
  if(c[i+1][n-1]==1){
    c[i+1][n-1]=2;
    deep(i+1,n-1);
  }
  if(c[i-1][n+1]==1){
    c[i-1][n+1]=2;
    deep(i-1,n+1);
  }
  if(c[i-1][n-1]==1){
    c[i-1][n-1]=2;
    deep(i-1,n-1);
  }
}

int main(){
  while(1){
    for(int i=0;i<51;i++){
      for(int n=0;n<51;n++){
          c[i][n]=0;
      }
    }
    int w,h;
    int num=0;

    scanf("%d%d",&w,&h);
    if(w==0&&h==0)break;

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

    for(int i=0;i<h;i++){
      for(int n=0;n<w;n++){
          if(c[i][n]==1){
            num++;
            deep(i,n);
          }
      }
    }

    printf("%d\n",num);
  }
  return 0;
}

C++: #include<bits/stdc++.h>
#include<string>
#include<vector>
using namespace std;
typedef pair<int, int>P;
typedef long long ll;
#define rep(i,n)for(ll i=0;i<n;++i)
#define exrep(i, a, b) for(ll i = a; i <= b; i++)
#define out(x) cout << x << endl
#define exout(x) printf("%.10f\n", x)
#define chmax(x, y) x = max(x, y)
#define chmin(x, y) x = min(x, y)
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define pb push_back
#define re0 return 0
const ll mod = 1000000007;
const ll INF = 1e16;
const ll MAX_N = 100010;
//max=({});
//条件式が真ならwhileの中身を回し続ける
//printf("%d\n", ans);

//pairの入力
//vector<pair<ll, ll>>work(n);
//rep(i, n) {
//	ll a, b;
//	cin >> a >> b;
//	work[i] = make_pair(a, b);
//for(auto p:mp)(mapの探索)
//printf("%.10f\n",なんちゃら)
//最大公約数
ll gcd(ll x, ll y) {
	return y ? gcd(y, x % y) : x;
}

ll lcm(ll x, ll y) {
	if (x == 0 || y == 0)return 0;
	return (x / gcd(x, y) * y);
}

//素因数分解
map<ll, ll>ins;
void facterize(ll n) {
	ll a = 2;
	while (n >= a * a) {
		if (n % a == 0) {
			ins[a]++;
			ins[a] = ins[a] % 1000000007;
			n /= a;
		}
		else {
			a++;
		}
	}
	ins[n]++;
}

int keta(int x) {
	int y = 0;
	while (x > 0) {
		y++;
		x /= 10;
	}
	return y;
}

ll dx[8] = { 0,0,-1,1 };
ll dy[8] = { -1,1,0,0 };
ll dp[1010][1010];
ll land[101][101];
bool flag[101][101];
ll h, w;

void dfs(ll y, ll x) {
	flag[y][x] = false;
	for (ll dx = -1;dx <= 1;++dx) {
		for (ll dy = -1;dy <= 1;++dy) {
			if (0 <= y + dy && y + dy < h && 0 <= x + dx && x + dx < w && flag[y + dy][x + dx]) {
				dfs(y + dy, x + dx);
			}
		}
	}
	return;
}

//long longしか使わない
int main() {
	while (cin >> w >> h,w||h) {
		for (ll i = 0;i < h;++i) {
			for (ll j = 0;j < w;++j) {
				cin >> land[i][j];
				if (land[i][j])flag[i][j] = true;
			}
		}
		ll ans = 0;
		for (ll i = 0;i < h;++i) {
			for (ll j = 0;j < w;++j) {
				if (flag[i][j]) {
					dfs(i, j);
					ans++;
				}
			}
		}
		cout << ans << endl;
	}
	return 0;
}

C++: #include <iostream>
#include <iomanip>
#include <utility>
#include <cmath>
#include <random>
#include <vector>
#include <map>
#include <set>
#include <deque>
#include <queue>
#include <stack>
#include <string>
#include <algorithm>
using namespace std;

#define rep(i,n) for(int i = 0; i<n; ++i)
#define REP(i,n) for(int i = 1; i<=n; ++i)
#define all(x) begin(x),end(x)
typedef long long ll;
typedef pair<int,int> ip;
typedef pair<ll,ll> lp;
const int inf = 1001001000;
const ll INF = 1LL<<60;
const int MOD = (int)1e9 + 7;

int d8x[8] = {0,1,1,1,0,-1,-1,-1};
int d8y[8] = {1,1,0,-1,-1,-1,0,1};

int m[55][55];
int w,h;

void dfs(int i, int j){
	m[i][j] = 0;
	rep(c,8){
		int dy = i+d8y[c], dx = j+d8x[c];
		if(1<=dx && dx<=w && 1<=dy && dy<=h && m[dy][dx] == 1){
			dfs(dy,dx);
		}
	}
	return ;
}

int main(){
	while(true){
		int ans = 0;
		cin>>w>>h;
		if(w == 0 && h == 0)break;
		REP(i,h)REP(j,w)cin>>m[i][j];
		REP(i,h)REP(j,w){
			if(m[i][j] == 1){
				++ans;
				dfs(i,j);
			}
		}
		cout<<ans<<endl;
	}
	return 0;
}

C++: #define _USE_MATH_DEFINES
#include <bits/stdc++.h>
#define USE_LLONG_AS_INT
#ifdef USE_LLONG_AS_INT
#define int long long
#define inf (1ll<<60)
#else
#define inf (1<<30)
#endif
#define rep(i,n) for(int i=0;i<n;i++)
#define Rep(i,a,b) for(int i=a;i<b;i++)
#define REP(i,a,b) for(int i=a;i<=b;i++)
#define rev(i,n) for(int i=(n)-1;i>=0;i--)
#define vi vector<int>
#define vvi vector<vi>
#define pb push_back
#define pi pair<int,int>
#define vp vector<pair<int,int>>
#define mp make_pair
#define all(v) (v).begin(),(v).end()
#define fi first
#define se second
#define MEMSET(a) memset(a,0,sizeof(a))
#define Yes(f) cout<<(f?"Yes":"No")<<endl
#define yes(f) cout<<(f?"yes":"no")<<endl
#define YES(f) cout<<(f?"YES":"NO")<<endl
#define SORT(v) sort(all(v))
#define RSORT(v) sort(all(v), greater<int>())

using namespace std;

const int mod=1e9+7;
const string sp=" ";

void run();

void init() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout<<fixed<<setprecision(12);
}

signed main(){
    init();
    run();
    return 0;
}

bool is_valid(int h,int w,int i,int j){
    return 0<=i&&i<h&&0<=j&&j<w;
}

void run(){
    int w,h;
    cin>>w>>h;
    if(!w)return;
    vvi c(h,vi(w));
    rep(i,h)rep(j,w)cin>>c[i][j];
    bool visited[h][w]={};
    queue<pi> q;
    int ans=0;
    int dx[]={1,1,0,-1,-1,-1,0,1},dy[]={0,1,1,1,0,-1,-1,-1};
    rep(i,h){
        rep(j,w){
            if(c[i][j]){
                ans++;
                q.push({i,j});
                visited[i][j]=true;
                while(!q.empty()){
                    pi p=q.front();
                    q.pop();
                    int y=p.fi,x=p.se;
                    c[y][x]=0;
                    rep(k,8){
                        int ny=y+dy[k],nx=x+dx[k];
                        if(is_valid(h,w,ny,nx)&&c[ny][nx]&&!visited[ny][nx]){
                            visited[ny][nx]=true;
                            q.push({ny,nx});   
                        }
                    }
                }
            }
        }
    }
    cout<<ans<<endl;
    run();
}