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: if __name__ == '__main__':
    while 1:
        w,h = list(map(int,input().strip().split()))
        if w == h ==0:break
        imap = [list(map(int,input().strip().split())) for _ in range(h)]
        visited = []
        count = 0
        for j in range(h):
            for i in range(w):
                stack =[]
                if not (j,i) in visited and imap[j][i] == 1:
                    count +=1
                    stack.append((j,i))
                    visited.append(((j,i)))
                while len(stack) !=0:
                    y,x = stack.pop()
                    if y>0 and imap[y-1][x] == 1 and not (y-1,x) in visited:
                        visited.append((y-1,x))
                        stack.append((y-1,x))
                    if x>0 and imap[y][x-1] == 1 and not (y,x-1) in visited:
                        visited.append(((y,x-1)))
                        stack.append((y,x-1))
                    if y>0 and x>0 and imap[y-1][x-1] == 1 and not (y-1,x-1) in visited:
                        visited.append((y-1,x-1))
                        stack.append((y-1,x-1))
                    if y>0 and x<w-1 and imap[y-1][x+1] ==1 and not (y-1, x+1) in visited:
                        visited.append((y-1, x+1))
                        stack.append((y-1, x+1))
                    if y <h-1 and x>0 and imap[y+1][x-1] ==1 and not (y+1,x-1) in visited:
                        visited.append((y+1,x-1))
                        stack.append((y+1,x-1))
                    if y < h-1 and x < w-1 and imap[y+1][x+1] ==1and not (y+1,x+1) in visited:
                        visited.append((y+1,x+1))
                        stack.append((y+1,x+1))
                    if y < h-1 and imap[y+1][x]== 1 and not (y+1,x) in visited:
                        visited.append((y+1,x))
                        stack.append((y+1,x))
                    if x < w-1 and imap[y][x+1] == 1 and not (y,x+1) in visited:
                        visited.append((y,x+1))
                        stack.append((y,x+1))
        print(count)

Python: # -*- coding:utf-8 -*-
def solve():
    import sys
    sys.setrecursionlimit(100*100)

    anss = []
    while True:
        W, H = list(map(int, input().split()))

        if W==0 and H==0:
            break

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

        visited = [[0 for _ in range(W)] for __ in range(H)]  # 探索済みか？

        def dfs(h, w, depth):
            if w<0 or h<0 or w>=W or h>=H:
                return 0

            if visited[h][w] == 1:
                return 0
            visited[h][w] = 1

            if grid[h][w] == 0:
                return 0

            ret = 0
            for hh in range(h-1, h+2):
                for ww in range(w-1, w+2):
                    ret += dfs(hh, ww, depth+1)

            return ret+depth

        ans = 0
        for h in range(H):
            for w in range(W):
                if dfs(h, w, grid[h][w]) != 0:
                    ans += 1

        anss.append(ans)

    for ans in anss:
        print(ans)


if __name__ == "__main__":
    solve()

Python: def dfs(island, r, c):
    stack = [(r, c)]
    ans = 0
    while stack:
        r, c = stack.pop()
        if r < 0 or r >= len(island) or c < 0 or c >= len(island[r]):
            continue
        if island[r][c] == 0:
            continue
        ans += 1
        island[r][c] = 0
        for rr in range(-1, 2):
            for cc in range(-1, 2):
                if rr == 0 and cc == 0:
                    continue
                stack.append((r+rr, c+cc))
    return ans


def solve(w, h):
    island = []
    for _ in range(h):
        island.append(list(map(int, input().split())))
    cnt = 0
    for r in range(h):
        for c in range(w):
           if dfs(island, r, c) > 0:
               cnt += 1
    print(cnt)

while True:
    w, h = map(int, input().split())
    if w == 0 and h == 0:
        break
    solve(w, h)