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;

vector<vector<int>> m;
int xv[]={1,1,1,0,-1,-1,-1,0},yv[]={1,0,-1,-1,-1,0,1,1};


void bfs(int x,int y){
    stack<pair<int,int>> stk;
    m[x][y]=0;
    for(int i=0;i<8;i++){
        if(m[x+xv[i]][y+yv[i]]){
            stk.push(make_pair(x+xv[i],y+yv[i]));
        }
    }
    while(!stk.empty()){
        pair<int,int> tg=stk.top();
        stk.pop();
        bfs(tg.first,tg.second);
    }
    
}


void solve(int c,int r){
    int in,ans=0;
    m=vector<vector<int>>(r+2,vector<int>(c+2,0));
    for(int i=1;i<=r;i++){
        for(int j=1;j<=c;j++){
            cin>>in;
            m[i][j]=in;
        }
    }
    stack<pair<int,int>> stk;
    
    for(int i=1;i<=r;i++){
        for(int j=1;j<=c;j++){
            if(m[i][j]){
                ans++;
                bfs(i,j);
            }
        }
    }
    
    cout<<ans<<endl;
}

int main(void){
    int a,b;
    while(cin>>a>>b,a){
        solve(a,b);
    }
}

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

using namespace std;


int read_map(vector< vector <int> >& map,int &w, int &h){
  cin >> w >>  h;
  if (w == 0 && h == 0){
    return 0;
  }
  map.reserve(h);
  for (int i = 0; i < h ; ++i) map[i].resize(w);
  for (int i = 0; i < h; ++i)
  {
    for (int j = 0; j < w; ++j)
    {
      cin >> map[i][j];
    }
  }
  return 1;
}


bool island_check(vector<vector<int> >& map, int i, int j){
  if (map[i][j] == 1){
    return true;
  }
  return false;
}

void walk_island(vector<vector<int> >& map, int i, int j, int w, int h){
  int start_i, start_j;
  start_i = i;
  start_j = j;
  while (++j < w){
    if (island_check(map, i, j))
    {
      map[i][j] = 2;
    }else{
      break;
    }
  }
  j = start_j;
  while (--j >= 0){
    if (island_check(map, i, j))
    {
      map[i][j] = 2;
    }else{
      break;
    }
  }
  while (++i < h){
    if (island_check(map, i, j))
    {
      map[i][j] = 2;
    }else{
      break;
    }
  }
  i = start_i;
  while (--i >= 0){
    if (island_check(map, i, j))
    {
      map[i][j] = 2;
    }else{
      break;
    }
  }
  i = start_i;
  j = start_j;
  while (++i < h && ++j < w){
    if (island_check(map, i, j))
    {
      map[i][j] = 2;
    }else{
      break;
    }
  }
  i = start_i;
  j = start_j;
  while (--i >= 0 && ++j < w){
    if (island_check(map, i, j))
    {
      map[i][j] = 2;
    }else{
      break;
    }
  }
  i = start_i;
  j = start_j;
  while (--i >= 0 && --j >= 0){
    if (island_check(map, i, j))
    {
      map[i][j] = 2;
    }else{
      break;
    }
  }
  while (++i < h && --j >= 0){
    if (island_check(map, i, j))
    {
      map[i][j] = 2;
    }else{
      break;
    }
  }
}

int search_island_num(vector< vector <int> >& map, int w, int h){
  int island_count = 0;
  for (int i = 0; i < h; ++i)
  {
    for (int j = 0; j < w; ++j)
    {
      if(map[i][j] == 1){
        island_count++ ;
        map[i][j] = 2;
        walk_island(map, i, j, w, h);
      }
    }
  }
  return island_count;
}

int main(){
  vector< vector<int> > map;
  int w, h;
  while (read_map(map, w, h) != 0) {
    cout << search_island_num(map, w, h) << endl;
    map.clear();
  }
}

C++: #include <iostream>
#include <stack>
using namespace std;

#define PIAR pair<int, int>

struct pos{
    int x;
    int y;
};

int main(){
    int w, h;
    while(cin >> w >> h, w != 0 && h != 0){
        int field[52][52] = {{0}};
        for(int i = 1; i <= h; i++){
            for(int j = 1; j <= w; j++){
                cin >> field[i][j];
            }
        }

        stack<PIAR> st;
        int island = 0;
        int dx[] = {-1,  0, 1, 0, -1,  1, 1, -1};
        int dy[] = {0 , -1, 0, 1, -1, -1, 1,  1};
        for(int i = 1; i <= h; i++){
            for(int j = 1; j <= w; j++){
                //島を探す
                if(field[i][j] == 1){
                    st.push(PIAR(j, i));
                    field[i][j] = 0;
                    while(!st.empty()){
                    	int x = st.top().first;
                    	int y = st.top().second;
                        st.pop();
                        for(int k = 0; k < 8; k++){
                            int nextX = x + dx[k];
                            int nextY = y + dy[k];
                            if(field[nextX][nextY] == 1){
                                st.push(PIAR(nextX, nextY));
                                field[nextX][nextY] = 0;
                            }
                        }
                    }
                    island++;
                }

            }
        }

        cout << island << endl;
    }
}

C++: #include <cstdio>

int w, h;
int data[64][64];
int movex[] = {-1, -1, -1, 0, 0, 1, 1, 1};
int movey[] = {-1, 0, 1, -1, 1, -1, 0, 1};

void dfs(int x, int y);

int main(void)
{	
	while (scanf("%d %d", &w, &h)){
		if (w == 0 && h == 0) break;
		
		for (int i = 0; i < 64; i++){
			for (int j = 0; j < 64; j++){
				data[i][j] = 0;
			}
		}
		
		for (int i = 1; i <= h; i++){
			for (int j = 1; j <= w; j++){
				scanf("%d", &data[i][j]);
			}
		}
		
		int res = 0;
		for (int i = 0; i < 64; i++){
			for (int j = 0; j < 64; j++){
				if (data[i][j] == 1){
					dfs(i, j);
					res++;
				}
			}
		}
		
		printf("%d\n", res);
	}
	
	return (0);
}

void dfs(int x, int y)
{
	data[x][y] = 0;
	
	for (int i = 0; i < 8; i++){
		if (data[x + movex[i]][y + movey[i]] == 1){
			dfs(x + movex[i], y + movey[i]);
		}
	}
	
	return;
}

C++: #include <iostream>
#include <algorithm>
#include <vector>
using namespace std;
//int cnt = 0;

void depth_search(int ,int,vector< vector<int> > &);
void show(vector<vector <int> > &umi){
  return ;
  cout << "---------------------------" << endl;
  for(int i = 0;i < umi[0].size();i++){
    for(int j = 0;j < umi.size();j++){
      cout << umi[j][i];
    }
    cout << endl;
  }
    cout << "---------------------------" << endl;
  
}
int main(){
  int w,h;
  while(true){
    cin >> w;
    cin >> h;
    if(w == 0 && h == 0)return 0;
    vector< vector<int> > umi(w,vector<int>(h));
    //    cout << "aaaaaaaaaa" << endl;
    for(int i = 0;i < h;i++){
      for(int j = 0;j < w;j++){
	cin >> umi[j][i];

      }
    } 

    int cnt = 0;
    for(int i = 0;i < w;i++){
      for(int j = 0;j < h;j++){
	if( umi[i][j] == 1){
	  cnt++;
	  umi[i][j] = 3;
	  depth_search(i,j,umi);
	  show(umi);

	}
      }
    }
    cout << cnt << endl;
  }
  return 0;
}
void depth_search(int x,int y,vector< vector<int> > &umi){
  int dx[3] = {0,1,-1};
  int dy[3] = {0,1,-1};
  for(int i = 0;i < 3;i++){
    for(int j = 0;j < 3;j++){
      if(!(x+dx[i] == -1
	 ||x+dx[i] == umi.size()
	 ||y+dy[j] == -1
	 ||y+dy[j] == umi[0].size())
	 && (umi[x+dx[i]][y+dy[j]] == 1)
	 && !(dx[i] == 0 && dy[j] == 0)){
	umi[x+dx[i]][y+dy[j]] = 3;
	depth_search(x+dx[i],y+dy[j],umi);
	
      }
    }
  }
}