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<algorithm>

using namespace std;

int res, land[1080][1080];
int xs[] = {1, 1, 0, -1, -1, -1, 0, 1};
int ys[] = {0, 1, 1, 1, 0, -1, -1, -1};
void dfs(int x, int y){
	land[x][y] = 0;
	for(int i = 0;i < 8;i++){
		int tx = x + xs[i];
		int ty = y + ys[i];
		if(land[tx][ty])dfs(tx, ty);
	}
}

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

C++: #include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
int map[60][60];
int main(void) {
	vector<int> list;
	for (;;) {
		int w, h;
		cin >> w >> h;
		if (!(w&&h))return 0;
		int cnt = 1;
		for (int i = 0; i < h; i++) {
			for (int j = 0; j < w; j++) {
				int buf;
				cin >> buf;
				map[i][j] = (buf?cnt++:0);
			}
		}
		bool update = true;
		for (;update;){
			cnt = 0;
			update = false;
			for (int i = 0; i < h; i++) {
				for (int j = 0; j < w; j++) {
					if (!map[i][j])continue;
					for (int n = max(0, i - 1); n <= min(h-1, i + 1); n++) {
						for (int m = max(0, j - 1); m <= min(w-1, j + 1); m++) {
							if (!map[n][m])continue;
							if (map[i][j]>map[n][m]) {
								map[i][j] = map[n][m];
								update = true;
							}
						}
					}
				}
			}
		}
		vector<int> num;
		for (int i = 0; i < h; i++) {
			for (int j = 0; j < w; j++) {
				num.push_back(map[i][j]);
			}
		}
		sort(num.begin(), num.end());
		num.erase(unique(num.begin(),num.end()),num.end());
		cout << num.size()-1<<endl;
	}
	return 0;
}

C++: #include<queue>
#include<cstdio>
#include<utility>
using namespace std;
typedef pair<int, int> P;
int main() {
	int W, H;
	int i, j, k;
	int map[50][50];
	int vector[8][2] = {{1, 0}, {0, 1}, {-1, 0}, {0, -1}, {1, 1}, {1, -1}, {-1, 1}, {-1, -1}};
	int count;
	queue<P> q;
	while (1) {
		scanf("%d %d", &W, &H);
		if (!(W||H)) break;
		count = 0;
		for (i = 0; i < H; i ++) for (j = 0; j < W; j ++) scanf("%d", &map[i][j]);
		for (i = 0; i < H; i ++) {
			for (j = 0; j < W; j ++) {
				if (map[i][j]) {
					map[i][j] = 0; count ++;
					q.push(P(i, j));
					while (!q.empty()) {
						P p = q.front(); q.pop();
						int x, y;
						for (k = 0; k < 8; k ++) {
							x = p.first + vector[k][0]; y = p.second + vector[k][1];
							if (-1 < x && x < H && -1 < y && y < W && map[x][y]) {
								q.push(P(x, y));
								map[x][y] = 0;
							}
						}
					}
				}
			}
		}
		printf("%d\n", count);
	}
	return 0;
}

C++: #include <iostream>
using namespace std;
int w,h;
int in[100][100];
bool seen[100][100];
int ans =0;

void solve(int i,int j){
    //cout << i << " " << j << endl;
    if(i < 0 || j < 0 || i >= h || j >= w){
        return;
    }
    if(seen[i][j]){
        return;
    }
    if(in[i][j] == 0){
        return;
    }
    seen[i][j] = true;
    solve(i-1,j-1);
    solve(i-1,j);
    solve(i-1,j+1);
    solve(i,j-1);
    solve(i,j+1);
    solve(i+1,j-1);
    solve(i+1,j);
    solve(i+1,j+1);

}
int main(){
    while(1){
    cin >> w >> h;
    if(w == 0 && h == 0){
        break;
    }
    for(int i=0;i<h;i++){
        for(int j=0;j<w;j++){
            cin >> in[i][j];
            seen[i][j] = false;
        }
    }
    ans = 0;
    for(int i=0;i<h;i++){
        for(int j=0;j<w;j++){
            if(seen[i][j] == true || in[i][j] == 0){
            }
            else{
                solve(i,j);
                ans++;
            }
            
        }
    }
   
     cout << ans << endl;
    }
    return 0;
}

C++: #define _USE_MATH_DEFINES
#include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < (n); i++)
#define YES(n) cout << ((n) ? "YES" : "NO") << endl
#define Yes(n) cout << ((n) ? "Yes" : "No") << endl

using namespace std;

typedef long long ll;
typedef pair<int, int> P;
typedef pair<ll, ll> LP;

const int MOD = 1e9 + 7;
const int INF = 1e9;
const ll LINF = 1e18;
const int dx[4] = {1, 0, -1, 0};
const int dy[4] = {0, 1, 0, -1};
const int ddx[8] = {1, 1, 0, -1, -1, -1, 0, 1};
const int ddy[8] = {0, 1, 1, 1, 0, -1, -1, -1};

int gcd(int a, int b) {
    if (b == 0)
        return a;
    return gcd(b, a % b);
}

int lcm(int a, int b) { return a * b * gcd(a, b); }

bool compareP(pair<int, int> a, pair<int, int> b) {
    if (a.second != b.second) {
        return a.second < b.second;
    } else {
        return a.first < b.first;
    }
}

int w, h;
int mp[50][50];

void dfs(int h2, int w2) {
    mp[h2][w2] = 0;
    rep(i, 8) {
        int nw = w2 + ddx[i];
        int nh = h2 + ddy[i];
        if (nw >= 0 && nw < w && nh >= 0 && nh < h && mp[nh][nw] == 1)
            dfs(nh, nw);
    }
}

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