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<bits/stdc++.h>
using namespace std;
using ll=long long;
#define fi first
#define se second
using Graph=vector<vector<int>>;
using P=pair<int,int>;
#define mp make_pair

void dfs(int u,int v,Graph graph,Graph &d,int flag)
{
	int h,w;
	h=graph.size();
	w=graph[0].size();
	int n=graph.size();
	d[u][v]=flag;
	vector<P> around={mp(u-1,v),mp(u+1,v),mp(u-1,v-1),mp(u-1,v+1),mp(u,v+1),mp(u,v-1),mp(u+1,v+1),mp(u+1,v-1)};
	for (int i=0;i<8;i++)
	{
		int x=around[i].fi,y=around[i].se;
		if (0<=x&&x<h && 0<=y&&y<w)
		{
			if (graph[x][y]==1 && d[x][y]==-1)
			{
				//cout << x << y << endl;
				dfs(x,y,graph,d,flag);
			}

		}
	}
}

int main()
{
	vector<int> ans;
	while (true)
	{
		int w,h;cin >> h >> w;
		if (w==0 && h==0) break;
		Graph graph(w,vector<int> (h,0)),d(w,vector<int> (h,0));
		for (int i=0;i<w;i++)
		{
			for (int j=0;j<h;j++)
			{
				cin >> graph[i][j];
				if (graph[i][j]==1) d[i][j]=-1;
			}
		}
		int flag=1;
		for (int i=0;i<w;i++)
		{
			for (int j=0;j<h;j++)
			{
				if (d[i][j]==-1)
				{
					dfs(i,j,graph,d,flag);
					flag++;
				}
			}
		}
		ans.push_back(flag-1);
	}
	for (int i=0;i<ans.size();i++) cout << ans[i] << endl;
	return 0;
}

C++: #include <cstdio>
#define f(n)for(int i=0;i<n;i++)
#define s(w)scanf("%d",&w);
int a,n,m,d[99][99],u[16]={-1,-1,-1,0,0,1,1,1,-1,0,1,-1,1,-1,0,1};void k(int x,int y){if(d[x][y]){d[x][y]=0;f(8)k(x+u[i],y+u[i+8]);}}int main(){a=0;s(n)s(m)if(n==0)return 0;f(9801)d[0][i]=0;f(n*m)s(d[i/n+1][i%n+1])f(n*m)if(d[i/n+1][i%n+1])a++,k(i/n+1,i%n+1);printf("%d\n",a);main();}

C++: #include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <cmath>
#include <cstdlib>
#include <tuple>
using namespace std;
using ll=long long;
using R=double;

int W,H;

int t[50][50];

void visit(int h,int w){
  t[h][w]=0;
  for(int nh=h-1;nh<h+2;nh++){
    for(int nw=w-1;nw<w+2;nw++){
      if(t[nh][nw]==1&&0<=nh&&0<=nw&&nh<H&&nw<W)visit(nh,nw);
    }
  }
}

int main(void){
  int a,b,c,n;
  while(1){
    cin>>W>>H;
    c=0;
    if(W==0&&H==0)break;
    for(int i=0;i<H;i++){
      for(int j=0;j<W;j++){
    cin>>t[i][j];
      }
    }
    for(int i=0;i<H;i++){
      for(int j=0;j<W;j++){
    if(t[i][j]==1){
      c++;
      visit(i,j);
    }
      }
    }
    cout<<c<<endl;
  }
}

C++: #include <iostream>
#define REP(i,a,b) for(int i = (a); i < (b); i++)
#define rep(i,a) REP(i,0,a)
using namespace std;

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

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

void dfs(int x,int y) {
    c[y][x] = 0;
    
    rep(i,8) {
        int nx = x+dx[i], ny = y+dy[i];
        if (0 <= nx && nx < w && 0 <= ny && ny < h && c[ny][nx] == 1) dfs(nx,ny);
    }
}
    
int main(void){
    while (1) {
        cin >> w >> h;
        if (w == 0 && h == 0) break;
        rep(y,h) rep(x,w) cin >> c[y][x];
        
        int ans = 0;        
        rep(y,h)
            rep(x,w)
                if (c[y][x] == 1) {
                    dfs(x,y);
                    ans++;
                }

        cout << ans << endl;
    }
    return 0;
}

C++: #include<iostream>
#include<vector>
#include<stack>
#include<queue>
#include<utility>
using namespace std;
bool find1(vector< vector<int> >& C,vector< vector<int> >& check,int* findh,int* findw)
{
  for(int i = 0;i < C.size();++i)
    for(int j = 0;j < C[0].size();++j)
      if(C[i][j] == 1 && check[i][j] == 0){
	*findh = i;
	*findw = j;
	return true;
      }
  return false;
}
bool find2(vector< vector<int> >& C,vector< vector<int> >& check,int* findh,int* findw)
{
  if(C[*findh - 1][*findw - 1] == 1 && check[*findh - 1][*findw - 1] == 0){
    *findh -= 1;
    *findw -= 1;
    return true;
  }
  else if(C[*findh - 1][*findw] == 1 && check[*findh - 1][*findw] == 0){
    *findh -= 1;
    return true;
  }
  else if(C[*findh - 1][*findw + 1] == 1  && check[*findh - 1][*findw + 1] == 0){
    *findh -= 1;
    *findw += 1;
    return true;
  }
  else if(C[*findh][*findw - 1] == 1 && check[*findh][*findw - 1] == 0){
    *findw -= 1;
    return true;
  }
  else if(C[*findh][*findw + 1] == 1 && check[*findh][*findw + 1] == 0){
    *findw += 1;
    return true;
  }
  else if(C[*findh + 1][*findw - 1] == 1 && check[*findh + 1][*findw - 1] == 0){
    *findh += 1;
    *findw -= 1;
    return true;
  }
  else if(C[*findh + 1][*findw] == 1 && check[*findh + 1][*findw] == 0){
    *findh += 1;
    return true;
  }
  else if(C[*findh + 1][*findw + 1] == 1 && check[*findh + 1][*findw + 1] == 0){
    *findh += 1;
    *findw += 1;
    return true;
  }
  else return false;
}
int main()
{
  int w,h,findh,findw;
  stack< pair<int,int> > finish;
  queue<int> answer;
  while(cin >> w >> h && !(w == 0 && h == 0)){
    int howmany = 0;
    vector< vector<int> > C(h + 2,vector<int>(w + 2,0)),check(h + 2,vector<int>(w + 2,0)); 
    for(int i = 1;i <= h;++i)
      for(int j = 1;j <= w;++j)
	cin >> C[i][j];
    while(find1(C,check,&findh,&findw)){
      check[findh][findw] = 1;
      finish.push(make_pair(findh,findw));
      while(!finish.empty()){
	findh = finish.top().first;
	findw = finish.top().second;
	while(find2(C,check,&findh,&findw)){
	  finish.push(make_pair(findh,findw));
	  check[findh][findw] = 1;
	}
	finish.pop();
      }
      ++howmany;
    }
    answer.push(howmany);
  }
  for(;!answer.empty();answer.pop())
    cout << answer.front() << endl;
}

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

using namespace std;

void del(int x, int y);

vector< vector<int> > arr;
int w, h;

int main(){
	
	while(cin >> w >> h, w | h){
		int ans = 0;
		arr.resize(h);
		for(int i = 0; i < h; i++){
			arr[i].resize(w);
		}
		
		for(int i = 0; i < h; i++){
			for(int j = 0; j < w; j++){
				cin >> arr[i][j];
			}
		}
		
		for(int i = 0; i < h; i++){
			for(int j = 0; j < w; j++){
				if(arr[i][j] == 1){
					del(i, j);
					ans++;
				}
			}
		}
				
		
		cout << ans << endl;
		arr.clear();
	}
	
	return 0;
	
}

void del(int x, int y){
	arr[x][y] = 0;	
	
	if(x + 1 < h && arr[x + 1][y] == 1){
		del(x + 1, y);
	}
	if(y + 1 < w && arr[x][y + 1] == 1){
		del(x, y + 1);
	}
	if(x - 1 > -1 && arr[x - 1][y] == 1){
		del(x - 1, y);
	}
	if(y - 1 > -1 && arr[x][y - 1] == 1){
		del(x, y - 1);
	}
	if(x + 1 < h && y + 1 < w && arr[x + 1][y + 1] == 1){
		del(x + 1, y + 1);
	}
	if(x - 1 > -1 && y + 1 < w && arr[x - 1][y + 1] == 1){
		del(x - 1, y + 1);
	}
	if(x - 1 > -1 && y - 1 > -1 && arr[x - 1][y - 1] == 1){
		del(x - 1, y - 1);
	}
	if(x + 1 < h && y - 1 > -1 && arr[x + 1][y - 1] == 1){
		del(x + 1, y - 1);
	}
	
	return;
}