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: import sys

def solve():
    while 1:
        w, h = map(int, sys.stdin.readline().split())

        if w == h == 0:
            return

        room = [[int(j) for j in sys.stdin.readline().split()] for i in range(h)]

        cnt = 0

        for i in range(h):
            for j in range(w):
                if room[i][j]:
                    cnt += 1
                    dfs(w, h, room, i, j)

        print(cnt)

def dfs(w, h, room, i, j):
    if i < 0 or i >= h or j < 0 or j >= w or (not room[i][j]):
        return

    room[i][j] = 0

    dfs(w, h, room, i + 1, j)
    dfs(w, h, room, i - 1, j)
    dfs(w, h, room, i, j + 1)
    dfs(w, h, room, i, j - 1)
    dfs(w, h, room, i + 1, j + 1)
    dfs(w, h, room, i + 1, j - 1)
    dfs(w, h, room, i - 1, j + 1)
    dfs(w, h, room, i - 1, j - 1)

if __name__ == '__main__':
    solve()

Python: import queue
def allvisited():
    for i in range(w):
        for j in range(h):
            if (visited[i][j]==False and s[i][j]=='1'):
                return (False,i,j)
    else:
         return (True,-1,-1)
        
def legal(pos):
    if(0<=pos[0]<w) and (0<=pos[1]<h) and s[pos[0]][pos[1]]=='1' and visited[pos[0]][pos[1]]==False:
        return True
    else:
        return False
    
d=[[0,1],[0,-1],[1,0],[-1,0],[1,1],[-1,1],[1,-1],[-1,-1]]
while(1):
    h,w=map(eval,input().split())
    if (w==0 and h==0): break
    s=[]
    for i in range(w):
        s.append(input().split())
    #print(s)
    Q=queue.Queue()
    visited=[]
    for i in range(w):
        visited.append([False]*h)
    #print(visited)
    count=0
    while(1):
        a=allvisited()
        if (a[0]==False):
            Q.put((a[1],a[2]))
            visited[a[1]][a[2]]=True
            count+=1
        else:
            break
        while(not Q.empty()):
            now=Q.get()
            for i in range(8):
                new=(now[0]+d[i][0],now[1]+d[i][1])
                if(legal(new)):
                    Q.put(new)
                    visited[new[0]][new[1]]=True
    print(count)

Python: from collections import deque

y = [1,1,1,0,0,-1,-1,-1]
x = [-1,0,1,-1,1,-1,0,1]

def main():
    w,h = 0,0
    c = []

    def check(i,j):
        return 0<=i and i<h and 0<=j and j<w

    def bfs(a,b):
        d = deque()
        d.append([a,b])
        while len(d):
            i,j = d.popleft()
            if not check(i,j):continue
            if c[i][j]==0:continue
            c[i][j]=0
            for k in range(8):
                d.append([i+y[k],j+x[k]])

    while True:
        w,h = map(int,input().split())
        if w==0 and h==0: break
        c = []
        res = 0
        for _ in range(h):
            c.append(list(map(int,input().split())))
        for i in range(h):
            for j in range(w):
                if c[i][j]==1:
                    bfs(i,j)
                    res+=1
        print(res)

if __name__ == '__main__':
    main()

Python: import sys
sys.setrecursionlimit(10**8)

def dfs_fill(m, x, y):
    if not (0 <= x < W and 0 <= y < H) or m[y][x] == "0":
        return False
    m[y][x] = "0"
    for dx in range(-1, 2):
        for dy in range(-1, 2):
            if dx == dy == 0:
                continue
            dfs_fill(m, x+dx, y+dy)

while True:
    W, H = map(int, input().split())
    if W == H == 0:
        break
    C = [input().split() for _ in range(H)]

    count = 0
    for y in range(H):
        for x in range(W):
            # print("\n".join(["".join(c) for c in C]))
            if C[y][x] == "1":
                count += 1
                dfs_fill(C, x, y)

    print(count)

Python: import sys, re
from collections import deque, defaultdict, Counter
from math import ceil, sqrt, hypot, factorial, pi, sin, cos, radians
from heapq import heappop, heappush, heapify, heappushpop
from itertools import permutations, combinations, product, accumulate
from operator import itemgetter, mul
from copy import deepcopy
from string import ascii_lowercase, ascii_uppercase, digits

def input(): return sys.stdin.readline().strip()
def INT(): return int(input())
def MAP(): return map(int, input().split())
def LIST(): return list(map(int, input().split()))
sys.setrecursionlimit(10 ** 9)
INF = float('inf')
MOD = 10 ** 9 + 7

dx = [0, 1, 0, -1, 1, 1, -1, -1]
dy = [1, 0, -1, 0, 1, -1, 1, -1]
def DFS(i, j):
	global w, h
	for x in range(8):
		nx = j + dx[x]
		ny = i + dy[x]
		if 0 <= nx <= w-1 and 0 <= ny <= h-1 and c[ny][nx]==1:
			c[ny][nx] = 0
			DFS(ny, nx)

ans = []
while 1:
	w, h = MAP()
	if [w, h] == [0, 0]:
		break
	c = [LIST() for _ in range(h)]

	count = 0
	for i in range(h):
		for j in range(w):
			if c[i][j] == 1:
				c[i][j] = 0
				DFS(i, j)
				count += 1
	ans.append(count)

for i in ans:
	print(i)

Python: import sys
sys.setrecursionlimit(1<<32)
def f(x,y):
    a[y][x]='0'
    for dx,dy in[[-1,0],[1,0],[0,-1],[0,1],[-1,-1],[1,-1],[-1,1],[1,1]]:
        dx+=x;dy+=y
        if 0<=dx<w and 0<=dy<h and a[dy][dx]=='1':f(dx,dy)
while 1:
    w,h=map(int,input().split())
    if w==0:break
    a=[list(input().split()) for _ in[0]*h];b=0
    for i in range(w):
        for j in range(h):
            if a[j][i]=='1':
                b+=1;f(i,j)
    print(b)