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>
#include<algorithm>

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

using namespace std;

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

void dfs(int x,int y) {
	map[x][y]=0;
	for(int i=-1;i<=1;i++) {
		for(int j=-1;j<=1;j++) {
			int nx = x+i;
			int ny = y+j;
			if(0<=nx&&nx<w && 0<=ny&&ny<h && map[nx][ny]==1)
				dfs(nx,ny);
		}
	}


}

void solve() {
	rep(i,51) rep(j,51) map[i][j]=0;

	rep(i,w) rep(j,h) cin>>map[i][j];

	int ans=0;
	rep(i,w) rep(j,h) {
		if(map[i][j]==1) {
			dfs(i,j);
			ans++;
		}
	}
	cout<<ans<<endl;
}

int main() {

	while (cin>>h>>w)
	{
		if(h+w==0) return 0;
		solve();

	}

	return 0;
}

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

#define iota(i,n,b,s) for(int i=int(b);i!=int((b)+(s)*(n));i+=(s))
#define range(i,n,m) iota(i,(((n)>(m))?((n)-(m)):((m)-(n))),(n),((n)>(m)?-1:1))
#define rep(i,n) iota(i,(n),0,1)
#define loop for(;;)

#define INF (1e9)
#define EPS (1e-9)
#define cons(a,b) (make_pair(a,b))
#define car(a) (a.first)
#define cdr(a) (a.second)
#define cadr(a) (car(cdr(a)))
#define cddr(a) (cdr(cdr(a)))
#define all(a) a.begin(), a.end()
#define trace(var) cerr<<">>> "<<#var<<" = "<<var<<endl;

typedef long long Integer;
typedef double Real;
typedef vector<int> vi;
typedef vector<string> vs;
typedef map<string,int> Dictionary;
const Real PI = acos(-1);

template<class S, class T>
ostream& operator<<(ostream& os, pair<S,T> p) {
  os << '(' << car(p) << ", " << cdr(p) << ')';
  return os;
}

template<class T>
ostream& operator<<(ostream& os, vector<T> v) {
  if (v.size() == 0) {
    os << "(empty)";
    return os;
  }
  os << v[0];
  for (int i=1, len=v.size(); i<len; ++i) os << ' ' << v[i];
  return os;
}

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

int main() {

  for (int w,h; cin >> w >> h, w && h; ) {
    vector<vector<int>> f(h, vector<int>(w));
    rep (i, h) {
      rep (j, w) {
        cin >> f[i][j];
      }}
    int cx = 0;
    rep (i, h) {
      rep (j, w) {
        if (f[i][j] == 0) continue;
        ++cx;

    stack<pair<int, int>> s;
    s.push(cons(i, j));

    while (!s.empty()) {
      auto x = s.top(); s.pop();
      if (car(x) < 0) continue;
      if (car(x) >= h) continue;
      if (cdr(x) < 0) continue;
      if (cdr(x) >= w) continue;
      if (f[car(x)][cdr(x)] == 0) continue;

      f[car(x)][cdr(x)] = 0;

      s.push(cons(car(x) + 1, cdr(x)));
      s.push(cons(car(x) - 1, cdr(x)));
      s.push(cons(car(x), cdr(x) + 1));
      s.push(cons(car(x), cdr(x) - 1));
      s.push(cons(car(x) + 1, cdr(x) - 1));
      s.push(cons(car(x) - 1, cdr(x) + 1));
      s.push(cons(car(x) + 1, cdr(x) + 1));
      s.push(cons(car(x) - 1, cdr(x) - 1));
    }

      }}

    cout << cx << endl;

  }
  return 0;
}

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

using namespace std;

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

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<queue>
#include<cstring>
using namespace std;
int x[90][90], col[90][90], h, w, c, i, j, k, l, p, q;
queue<int>Q, R;
int main() {
	while (true) {
		c = 0;
        memset(x,0,sizeof(x));
		memset(col, 0, sizeof(col));
		cin >> w >> h;
		if (h == 0) { break; }
		for (i = 0; i < h; i++) { for (j = 0; j < w; j++) { cin >> x[i][j]; } }
		for (i = 0; i < h; i++) {
			for (j = 0; j < w; j++) {
				if (x[i][j] == 1 && col[i][j] == 0) {
					c++;
					col[i][j] = c;
					Q.push(i * 100 + j);
					while (!Q.empty()) {
						while (!Q.empty()) {
							p = Q.front() / 100;
							q = Q.front() % 100;
							for (k = -1; k < 2; k++) {
								for (l = -1; l < 2; l++) {
									if (x[p + k][q + l] == 1 && col[p + k][q + l] == 0) {
										col[p + k][q + l] = c;
										R.push((p + k) * 100 + q + l);
									}
								}
							}
							Q.pop();
						}
						while (!R.empty()) {
							Q.push(R.front());
							R.pop();
						}
					}
				}
			}
		}
		cout << c << endl;
	}
}

C++: #include <iostream>
#include <vector>
using namespace std;
int d[3] = {0,1,-1};
void dfs(int x,int y,vector<vector<int> > &field){
  if((x < 0 || y < 0 || x >= field[0].size() || y >= field.size()) || field[y][x] == 0)return ;
  field[y][x] = 0;
  for(int i = -1;i <= 1;i++){
	for(int j = -1;j <= 1;j++){
	  if(i == 0 && j == 0)continue;
	  dfs(x+i,y+j,field);
	}
  }
  
}

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

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

struct Graph{
	vector<vector<int>> fld;
	
	Graph(int h,int w) : fld( h,vector<int>(w) ){}
	
	void dfs(int x, int y){
		
		fld.at(x).at(y) = 2;
		for(int i=-1; i<=1; i++){
			for(int j=-1; j<=1; j++){
				int h = fld.size();
				int w = fld.at(0).size();
				if(x+i<0||h-1<x+i||y+j<0||w-1<y+j) continue;
				if(fld.at(x+i).at(y+j)!=1) continue;
				dfs(x+i,y+j);
			}
		}
		return;
	}
	
};

int main() {
	while(1){
		int w,h;
		cin >> w >> h;
		if(w==0&&h==0) break;
		
		Graph graph(h,w);
		for(int i=0; i<h; i++){
			for(int j=0; j<w; j++){
				int s;
				cin >> s;
				graph.fld.at(i).at(j) =  s;
			}
		}
		
		int cnt{};
		for(int i=0; i<h; i++){
			for(int j=0; j<w; j++){
				if(graph.fld.at(i).at(j)==1) {
					graph.dfs(i,j);
					cnt++;
				}
				
			}
			
		}
		cout << cnt << endl;
	}
	
}