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)
	}
}

Python: #!/usr/bin/env python
# -*- coding: utf-8 -*-

def dfs(s,Map,H,W,c):
    dxdy = [(1,0),(-1,0),(0,1),(0,-1),(1,1),(-1,-1),(-1,1),(1,-1)]
    for i in range(8):
        Map[s[0]][s[1]] = c
        nextPos = (s[0]+dxdy[i][0],s[1]+dxdy[i][1])
        if nextPos[0] >= 0 and nextPos[1] >= 0 and nextPos[0] < H and nextPos[1] < W:
            if Map[nextPos[0]][nextPos[1]] == 1:
                dfs(nextPos,Map,H,W,c)

while True:
    W,H = map(int,input().split(" "))
    if W == 0 and H == 0:
        break
    Map = [list(map(int,input().split())) for i in range(0,H)]
    c = 1
    for i in range(H):
        for j in range(W):
            if Map[i][j] == 1:
                c += 1
                dfs((i,j),Map,H,W,c)
    print(c-1)

Python: def dfs(w,h,W,H,ID,islands,islandsID):
    if islands[h][w]==1 and islandsID[h][w]!=0:
        for i in range(-1,2):
            for j in range(-1,2):
                dw=w+i
                dh=h+j
                if dw>=0 and dw<W and dh>=0 and dh<H:
                    if islands[dh][dw]==1:
                        islandsID[dh][dw]=islandsID[h][w]
    if islands[h][w]==1 and islandsID[h][w]==0:
        for i in range(-1,2):
            for j in range(-1,2):
                dw=w+i
                dh=h+j
                if dw>=0 and dw<W and dh>=0 and dh<H:
                    if islands[dh][dw]==1:
                        islandsID[dh][dw]=ID
        ID+=1
    return ID

while True:
    islands=[]
    islandsID=[]
    ID=1
    W,H=map(int,input().split())
    if W==0:
        break
    for i in range(H):
        islandsID.append([0 for j in range(W)])
    for _ in range(H):
        islands.append(list(map(int,input().split())))
    for h in range(H):
        for w in range(W):
            ID=dfs(w,h,W,H,ID,islands,islandsID)
    print(ID-1)

Python: import itertools
import sys
sys.setrecursionlimit(5000)


class TestInput:
    @classmethod
    def input(self):
        TestInput.current += 1
        return TestInput.data.splitlines()[TestInput.current]
    current = -1
    data = '''\
2 2
0 1
1 0
5 4
1 0 1 0 0
1 0 0 0 0
1 0 1 0 1
1 0 0 1 0
0 0
'''


def read_input():
    # return TestInput.input()
    return input()


class IslandMap:
    moves = list(itertools.product([-1, 0, 1], [-1, 0, 1]))

    def __init__(self, w, h, c):
        self.w = w
        self.h = h
        self.c = c

    def dfs(self, p):
        self.c[p[0]][p[1]] = 0
        for m in IslandMap.moves:
            n = (p[0] + m[0], p[1] + m[1])
            if 0 <= n[0] < self.h and 0 <= n[1] < self.w:
                if self.c[n[0]][n[1]] == 1:
                    self.dfs(n)

    def solve(self):
        region = 0
        lattice = itertools.product(range(self.h), range(self.w))
        for p in lattice:
            if self.c[p[0]][p[1]] == 1:
                self.dfs(p)
                region += 1
        return region


while True:
    w, h = map(int, read_input().split())
    if w == 0 or h == 0:
        break
    c = [list(map(int, read_input().split())) for i in range(h)]
    island = IslandMap(w, h, c)
    print(island.solve())

Python: # -*- coding: utf-8 -*-
#150 島は幾つある？
h,w=1,1

count=0
anser=0

def search(x,y):
    #マップの外側か壁の場合は何もしない
    #print(x,y)

    global count
    count+=1
    if x<0 or x>w-1 or y<0 or y>h-1 or map_data[y][x]==0:
 
        return
        
    
    #以前に到達していたら何もしない
    if reached[y][x] ==0:
         return

    reached[y][x]=0
    
    #print("aa")



    search(x+1,y)#右
    search(x-1,y)#左
    search(x,y+1)#上
    search(x,y-1)#下
    search(x-1,y-1)
    search(x-1,y+1)
    search(x+1,y-1)
    search(x+1,y+1)



while h!=0 and w!=0: 
    anser=0
    count=1
    #グラフの入力方法------

    w,h=map(int ,raw_input().split())
    if h==0 and w==0:
        break

    map_data = [[0]*w for _ in range(h)]
    reached = [[1]*w for _ in range(h)]

    for i in range(h):
        ct = raw_input().split()
       
        for j in range(w):
            map_data[i][j] = int(ct[j])
            reached [i][j]=int(ct[j])
            if ct[j]==1:
                sx=j
                sy=i

    t=0
    a=0
    while a<=h:
       if 1 in reached[t%h]:         
            search(reached[t%h].index(1),t%h)
            anser+=1
            #print("count",count)
            count=1
            a=0
       elif count==h:
                break
       t+=1
       a+=1

    print(anser)

    #------

Python: #!/usr/bin/env python
# -*- coding: utf-8 -*-

def dfs(s,Map,H,W,c):
    dxdy = [(1,0),(-1,0),(0,1),(0,-1),(1,1),(-1,-1),(-1,1),(1,-1)]
    for i in range(len(dxdy)):
        Map[s[0]][s[1]] = c
        nextPos = (s[0]+dxdy[i][0],s[1]+dxdy[i][1])
        if nextPos[0] >= 0 and nextPos[1] >= 0 and nextPos[0] < H and nextPos[1] < W:
            if Map[nextPos[0]][nextPos[1]] == 1:
                dfs(nextPos,Map,H,W,c)

while True:
    W,H = map(int,input().split(" "))
    if W == 0 and H == 0:
        break
    Map = [list(map(int,input().split())) for i in range(0,H)]
    c = 1
    for i in range(H):
        for j in range(W):
            if Map[i][j] == 1:
                c += 1
                dfs((0,0),Map,H,W,c)
    print(c-1)

Python: #!python
# -*- coding: utf-8 -*-

import sys

import numpy as np

sys.setswitchinterval(10**8)


next_s = ((-1, 1), (0, 1), (1, 1),
          (-1, 0), (1, 0),
          (-1, -1), (0, -1), (1, -1))


def DFS(x, y):
    if not (0 <= x < W and 0 <= y < H):
        return
    if not map_[y, x]:
        return

    map_[y, x] = 0

    for dx, dy in next_s:
        DFS(x + dx, y + dy)


while True:
    W, H = map(int, input().split())
    if W == 0 and H == 0:
        break

    map_ = np.array([list(map(int, input().split())) for h in range(H)])
    # print(map_)
    island_num = 0
    while np.amax(map_):
        x = np.argmax(map_) % W
        y = np.argmax(map_) // W
        # print(map_)
        # print("x: {} | y: {}".format(x, y))
        DFS(x, y)
        island_num += 1

    print(island_num)