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: anslist = []
def sarch(i, j, visited):

    if 0 < i:
        if visited[i - 1][j] == 0:
            visited[i - 1][j] = 1
            sarch(i - 1, j, visited)
        if 0 < j:
            if visited[i - 1][j - 1] == 0:
                visited[i - 1][j - 1] = 1
                sarch(i - 1, j - 1, visited)
        if j < len(visited[0]) - 1:
            if visited[i - 1][j + 1] == 0:
                visited[i - 1][j + 1] = 1
                sarch(i - 1, j + 1, visited)

    if i < len(visited) - 1:
        if visited[i + 1][j] == 0:
            visited[i + 1][j] = 1
            sarch(i + 1, j, visited)
        if 0 < j:
            if visited[i + 1][j - 1] == 0:
                visited[i + 1][j - 1] = 1
                sarch(i + 1, j - 1, visited)
        if j < len(visited[0]) - 1:
            if visited[i + 1][j + 1] == 0:
                visited[i + 1][j + 1] = 1
                sarch(i + 1, j + 1, visited)

    if 0 < j:
        if visited[i][j - 1] == 0:
            visited[i][j - 1] = 1
            sarch(i, j - 1, visited)
    if j < len(visited[0]) - 1:
        if visited[i][j + 1] == 0:
            visited[i][j + 1] = 1
            sarch(i, j + 1, visited)
    return visited


while True:
    w, h = map(int, input().split())
    if w == 0 and h == 0:
        break
    grid = [list(map(int, input().split())) for j in range(h)]
    visited = [[0 for i in range(w)] for j in range(h)]
    starti = 0
    startj = 0
    for i in range(h):
        for j in range(w):
            if grid[i][j] == 0:
                visited[i][j] = -1
            else:
                visited[i][j] = 0

    i = 0
    j = 0
    cnt = 0
    ans = 0
    #print(visited)
    while True:
        if i >= h:
            i = 0
            j = 0
        while True:
            cnt += 1
            if j >= w:
                j = 0
                break
            #print(visited[i][j], 100100)
            if visited[i][j] == 0:
                ans += 1
                visited[i][j] = 1
                visited = sarch(i, j, visited)
                cnt = 0
            j += 1
        i += 1
        #print(cnt, visited)
        if cnt > w * h:
            #print(10)
            break
    anslist.append(ans)

for i in anslist:
    print(i)

Python: import sys
sys.setrecursionlimit(10**6)


def dfs(h, w):
    if visited[h][w]:
        return 0
    elif grid[h][w] == 0:
        visited[h][w] = True
        return 0
    else:
        visited[h][w] = True
        for m in moves:
            nh, nw = h + m[0], w + m[1]
            if nh < 0 or nw < 0 or nh >= H or nw >= W:
                continue
            else:
                dfs(nh, nw)
        return 1


moves = [[1, 0], [-1, 0], [0, 1], [0, -1], [1, 1], [-1, 1], [-1, -1], [1, -1]]


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

    grid = [list(map(int, input().split())) for _ in range(H)]

    visited = [[False] * W for _ in range(H)]

    cnt = 0
    for h in range(H):
        for w in range(W):
            cnt += dfs(h, w)

    print(cnt)

Python: import sys
sys.setrecursionlimit(3000)
def d(i,j):
    global count
    c[i][j]=1
    for k in range(3):
        for l in range(3):
            if 0<=i+k-1 and i+k<=h and 0<=j+l-1 and j+l<=w:
                if c[i+k-1][j+l-1]==0 and ma[i+k-1][j+l-1]==1:
                    d(i+k-1,j+l-1)
while(1):
    w,h=map(int,input().split())
    if w!=0 or h!=0:
        ma=[]
        for z in range(h):
            r=list(map(int,input().split()))
            ma.append(r)
        c=[[0]*w for e in range(h)]
        count=0
        for x in range(h):
            for y in range(w):
                if c[x][y]==0 and ma[x][y]==1:
                    d(x,y)
                    count+=1
        print(count)
    else:
        break
        break

Python: import collections,itertools,sys
def LI(): return list(map(int,sys.stdin.readline().rstrip().split()))
while 1:
    w,h = LI()
    if w==h==0:
        break
    ans = 0
    c = [LI() for _ in range(h)]
    seen = [[0]*w for _ in range(h)]
    stack = []
    dhdw = [[-1,-1],[-1,0],[-1,1],[0,-1],[0,1],[1,-1],[1,0],[1,1]]
    def dfs(H,W):
        seen[H][W] = 1
        stack.append([H,W])
        while stack:
            sh,sw = stack.pop()
            for dh,dw in dhdw:
                nh,nw = sh+dh,sw+dw
                if not(0<=nh<=h-1) or not(0<=nw<=w-1) or seen[nh][nw] or c[nh][nw]==0:
                    continue
                seen[nh][nw] = 1
                stack.append([nh,nw])
    for H,W in itertools.product(range(h),range(w)):
        if seen[H][W] or c[H][W]==0:
            continue
        ans += 1
        dfs(H,W)
    print(ans)