Go: // AOJ 1160: How Many Islands? http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=1160

package main

import (
	"bufio"
	"container/list"
	"fmt"
	"os"
	"strconv"
)

var SEA = 0
var LAND = 1

func nextInt(sc *bufio.Scanner) int {
	sc.Scan()
	v, _ := strconv.Atoi(sc.Text())
	return v
}

func discoverIslands(M, V [][]int, H, W int) int {
	// 島を探す
	queue := list.New()
	islands := 0
	for i := 1; i <= H; i++ {
		for j := 1; j <= W; j++ {
			// 訪問済みの土地ならスキップ
			if V[i][j] == 1 {
				continue
			}

			// 訪問中の土地が海なら訪問済みにしてスキップ
			if M[i][j] == SEA {
				V[i][j] = 1
				continue
			}

			// 未訪問の陸地が見つかったので
			// 島の数を1つ増やし、この陸地から辿れる陸地を訪問していく
			islands++
			queue.PushBack([]int{i, j})

			for queue.Len() > 0 {
				cur := queue.Remove(queue.Front()).([]int)
				h, w := cur[0], cur[1]
				if V[h][w] == 1 {
					continue
				}
				V[h][w] = 1

				// 全方向に未訪問の陸地がないか探索
				for v := -1; v <= 1; v++ {
					for l := -1; l <= 1; l++ {
						dh := h + v
						dw := w + l
						if M[dh][dw] == LAND && V[dh][dw] == 0 {
							queue.PushBack([]int{dh, dw})
						}
					}
				}
				/*
					if M[h-1][w] == LAND {
						queue.PushBack([]int{h - 1, w})
					}
					if M[h-1][w+1] == LAND {
						queue.PushBack([]int{h - 1, w + 1})
					}
					if M[h][w+1] == LAND {
						queue.PushBack([]int{h, w + 1})
					}
					if M[h+1][w+1] == LAND {
						queue.PushBack([]int{h + 1, w + 1})
					}
					if M[h+1][w] == LAND {
						queue.PushBack([]int{h + 1, w})
					}
					if M[h+1][w-1] == LAND {
						queue.PushBack([]int{h + 1, w - 1})
					}
					if M[h][w-1] == LAND {
						queue.PushBack([]int{h, w - 1})
					}
					if M[h-1][w-1] == LAND {
						queue.PushBack([]int{h - 1, w - 1})
					}
				*/
			}
		}
	}
	return islands
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	for {
		W, H := nextInt(sc), nextInt(sc)

		if W == 0 && H == 0 {
			break
		}
		// Initialize map and visted list
		M := make([][]int, H+2)
		V := make([][]int, H+2)
		for i := 0; i < H+2; i++ {
			M[i] = make([]int, W+2)
			V[i] = make([]int, W+2)
		}
		for i := 1; i <= H; i++ {
			for j := 1; j <= W; j++ {
				M[i][j] = nextInt(sc)
			}
		}

		islands := discoverIslands(M, V, H, W)

		fmt.Println(islands)
	}
}

Python: # aoj_how_meny_island.py
import sys
sys.setrecursionlimit(500000)
def printseen():
    for i in seen:
        print(i)

def dsf(h,w):
    seen[h][w]=True
    for i in dh:
        for j in dw:
            nh = h+i
            nw = w+j
            if canGo(nh,nw,i,j):
                dsf(nh,nw)
    return 1

def canGo(nh,nw,i,j):
#    print("going to ",nh,nw)
    # staying
    if i == 0 and j == 0:return False
    # out of range
    if nh < 0 or nw < 0 or nh >= H or nw >= W:return False
    # if you seen skip it
    if seen[nh][nw]:return False
    # if you meet sea skip it 
    if C[nh][nw] == "0" : return False
#    print("can go to ",nh,nw)
    return True

while True:
    W,H = map(int,input().split())
    if W==0 and H==0:
        exit()
    C = []
    for i in range(H):
        C.append(input().split())
    seen = [[False for _ in range(W)] for _ in range(H)]
    dh = [-1,0,1]
    dw = [-1,0,1]
    cnt = 0
    for h in range(H):
        for w in range(W):
            # すでに見てる場所と、海は見ない
            if not seen[h][w] and not C[h][w]=="0":
                cnt += dsf(h,w)
    print(cnt)

Python: import sys
sys.setrecursionlimit(10**6)
ans = []
while True:
    w, h = map(int, input().split())
    if w == 0 and h == 0:
        break
    c = [list(map(int, input().split())) for _ in range(h)]
    # print(*c, sep='\n')
    dx = [0, -1, 1]
    dy = [0, -1, 1]
    seen = [[0 for _ in range(w)] for _ in range(h)]
    cnt = 0
    def dfs(y, x, seen):
        seen[y][x] = 1
        # print(x, y, *seen,sep='\n')
        # print('\n')

        for i in range(3):
            for j in range(3):
                if i == 0 and j == 0:
                    continue
                if 0 <= x+dx[i] < w and 0 <= y+dy[j] < h:
                    if c[y+dy[j]][x+dx[i]] == 1 and seen[y+dy[j]][x+dx[i]] == 0:
                        dfs(y+dy[j], x+dx[i], seen)

    for i in range(h):
        for j in range(w):
            if not (seen[i][j] == 1 or c[i][j] == 0):
                dfs(i, j, seen)
                cnt += 1

    ans.append(cnt)

print(*ans, sep='\n')

Python: 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: import sys
import copy
sys.setrecursionlimit(10**7)
dx = [1,0,-1,0,1,1,-1,-1]
dy = [0,1,0,-1,1,-1,1,-1]
def dfs(MAP,w,h,x,y):
    MAP[y][x] = 0
    for dir in range(8):
        nx = x + dx[dir]
        ny = y + dy[dir]
        if nx < 0 or nx >= w or ny < 0 or ny >= h:
            continue
        if MAP[ny][nx] == 0:
            continue
        dfs(MAP,w,h,nx,ny)
ans = []
bool = True
while(bool):
    w,h = map(int,input().split())
    if w == 0 and h == 0:
        bool = False
        break
    c = [list(map(int,input().split())) for _ in range(h)]
    cnt = 0
    for i in range(h):
        for j in range(w):
            if c[i][j] == 1:
                cnt += 1
                dfs(c,w,h,j,i)
    ans.append(str(cnt))
for i in range(len(ans)):
    print(ans[i])

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

import sys

sys.setswitchinterval(10**9)


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 map_[y][x] == 0:
        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_ = [list(map(int, input().split())) for h in range(H)]
    island_num = 0
    for x in range(W):
        for y in range(H):
            if map_[y][x] == 1:
                DFS(x, y)
                island_num += 1
    print(island_num)