Go: package main

import (
	"bufio"
	"fmt"
	"io"
	"math"
	"os"
	"strconv"
)

var (
	readString func() string
	readBytes  func() []byte
	stdout     *bufio.Writer
)

func init() {
	readString, readBytes = newReadString(os.Stdin)
	stdout = bufio.NewWriter(os.Stdout)
}

func newReadString(ior io.Reader) (func() string, func() []byte) {
	r := bufio.NewScanner(ior)
	r.Buffer(make([]byte, 1024), math.MaxInt32)
	r.Split(bufio.ScanWords)

	f1 := func() string {
		if !r.Scan() {
			panic("Scan failed")
		}
		return r.Text()
	}
	f2 := func() []byte {
		return []byte(f1())
	}
	return f1, f2
}

func readInt() int {
	return int(readInt64())
}

func readInt64() int64 {
	i, err := strconv.ParseInt(readString(), 10, 64)
	if err != nil {
		panic(err.Error())
	}
	return i
}

func readFloat64() float64 {
	f, err := strconv.ParseFloat(readString(), 64)
	if err != nil {
		panic(err.Error())
	}
	return f
}

func printf(f string, args ...interface{}) (int, error) {
	return fmt.Fprintf(stdout, f, args...)
}

func println(args ...interface{}) (int, error) {
	return fmt.Fprintln(stdout, args...)
}

func eprintln(args ...interface{}) (int, error) {
	return fmt.Fprintln(os.Stderr, args...)
}

func eprintf(f string, args ...interface{}) (int, error) {
	return fmt.Fprintf(os.Stderr, f, args...)
}

func min(a, b int) int {
	if a < b {
		return a
	}
	return b
}

func min64(a, b int64) int64 {
	if a < b {
		return a
	}
	return b
}

func max(a, b int) int {
	if a < b {
		return b
	}
	return a
}

func max64(a, b int64) int64 {
	if a < b {
		return b
	}
	return a
}

func abs(a int) int {
	if a < 0 {
		return -a
	}
	return a
}

func abs64(a int64) int64 {
	if a < 0 {
		return -a
	}
	return a
}

func gcd(a, b int) int {
	if b == 0 {
		return a
	}
	return gcd(b, a%b)
}

func gcd64(a, b int64) int64 {
	if b == 0 {
		return a
	}
	return gcd64(b, a%b)
}

// readString() string
// readInt() int
// readInt64() int64
// readFloat64() float64

// -----------------------------------------------------------------------------

func main() {
	defer stdout.Flush()

	for {
		ans, ok := solve()
		if !ok {
			break
		}
		println(ans)
	}

}

func solve() (int, bool) {
	w := readInt()
	h := readInt()
	if w == 0 && h == 0 {
		return 0, false
	}

	c := make([][]int, h+2)
	c[0] = make([]int, w+2)
	c[h+1] = make([]int, w+2)
	for i := 1; i-1 < h; i++ {
		c[i] = make([]int, w+2)
		for j := 1; j-1 < w; j++ {
			c[i][j] = readInt()
		}
	}

	var ans int
	for i := 1; i-1 < h; i++ {
		for j := 1; j-1 < w; j++ {
			if 0 < c[i][j] {
				ans++
				dfs(c, i, j)
			}
		}
	}
	return ans, true
}

func dfs(c [][]int, y, x int) {
	c[y][x] = 0
	dx := []int{-1, 0, 1, -1, 1, -1, 0, 1}
	dy := []int{-1, -1, -1, 0, 0, 1, 1, 1}
	for i := range dx {
		nx := x + dx[i]
		ny := y + dy[i]
		if 0 < c[ny][nx] {
			dfs(c, ny, nx)
		}
	}
}

// -----------------------------------------------------------------------------

Python: import sys
sys.setrecursionlimit(200000)
readline = sys.stdin.buffer.readline


def dfs(C, h, w):
    # 一度訪ねた陸地は'0'(海)に置き換える
    C[h][w] = '0'
    for i in range(-1, 2):
        for j in range(-1, 2):
            if 0 <= h+i < len(C) and 0 <= w+j < len(C[0]) and C[h+i][w+j] == '1':
                dfs(C, h+i, w+j)


W, H = 1, 1
while W != 0 or H != 0:
    W, H = map(int, input().split())
    C = []
    for h in range(H):
        c = list(input().split())
        #c = readline().split()
        C.append(c)

    count = 0
    for h in range(H):
        for w in range(W):
            if C[h][w] == '1':
                dfs(C, h, w)
                count += 1
    if W != 0 or H != 0:
        print(count)

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

# 移動ベクトル
dx = [1, 1, 0, -1, -1, -1, 0, 1]
dy = [0, 1, 1, 1, 0, -1, -1, -1]

def dfs(h, w):
    seen[h][w] = True
    
    # 次の探索位置を取得
    for dir in range(8):
        nh, nw = h + dx[dir], w + dy[dir]
        if nh < 0 or nh >= H or nw < 0 or nw >= W: continue
        if field[nh][nw] == 0: continue
        if seen[nh][nw] == True: continue
        dfs(nh, nw)
        
while True:
    W, H = map(int, input().split())
    if W == 0 and H == 0:
        break
    
    field = [[int(i) for i in input().split()] for j in range(H)]

    seen = [[False for i in range(W)] for j in range(H)]

    count = 0
    for h in range(H):
        for w in range(W):
            if seen[h][w] == False and field[h][w] == 1:
                dfs(h, w)
                count += 1

    print(count)

Python: import sys

input = sys.stdin.buffer.readline
sys.setrecursionlimit(10 ** 7) 

count_list = []

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

    grid = [0] * (w + 2)
    for _ in range(h):
        grid += [0]
        grid += list(map(int, input().split()))
        grid += [0]
    grid += [0] * (w + 2)

    move = [-1, +1, -(w + 2) - 1, -(w + 2), -(w + 2) + 1, w + 2 - 1, w + 2, w + 2 + 1]
    visit = set()
    count = 0

    def search(x):
        if x not in visit:
            visit.add(x)
            for dx in move:
                y = x + dx
                if grid[y] == 0:
                    continue
                else:
                    search(y)

    for i in range((w+2) * (h+2)):
        if grid[i] == 0 or i in visit:
            continue
        count += 1
        search(i)
    count_list.append(count)

for i in range(len(count_list)):
    print(count_list[i])

Python: def dfs(tiles, W, H, x, y):
    tiles[y][x] = '0'
    for dx,dy in ((-1,-1), (-1,0), (-1,1), (0,-1), (0,1), (1,-1), (1,0), (1,1)):
        if 0<=x+dx<W and 0<=y+dy<H and tiles[y+dy][x+dx]=='1':
            dfs(tiles, W, H, x+dx, y+dy)
    return

def main():
    while True:
        W,H = [int(x) for x in input().split()]
        if W==0 and H==0:
            exit()
        tiles = [[c for c in input().split()] for h in range(H)]
        cnt = 0
        for h in range(H):
            for w in range(W):
                if tiles[h][w] == '1':
                    cnt += 1
                    dfs(tiles, W, H, w, h)
        print(cnt)

if __name__ == '__main__':
    main()

Python: 
dirs = [(-1,-1),(-1,0),(-1,1), (0,-1),(0,1), (1,-1),(1,0),(1,1)]

while True:
	w, h = map(int, input().split())
	if (w,h) == (0,0):
		break
	tile = [input().split() for i in range(h)]
	count = 0
	for i in range(h):
		for j in range(w):
			if tile[i][j] == '1':
				count += 1
				q = [(i,j)]
				while q:
					(x,y) = q.pop()
					for d in dirs:
						xx = x+d[0]
						yy = y+d[1]
						if (0 <= xx and xx < h) and (0 <= yy and yy < w):
							if tile[xx][yy] == '1':
								tile[xx][yy] = '0'
								q.append((xx,yy))
	print(count)

Python: import sys
sys.setrecursionlimit(2500)
w,h = map(int,input().split())
while not(w==h==0):
    m = [[0]*(w+2)]
    m += [[0]+list(map(int,input().split()))+[0] for i in range(h)]
    m += [[0]*(w+2)]
    g = [[] for i in range(w*h)]
    for i in range(1,h+1):
        for j in range(1,w+1):
            if m[i][j]==1:
                for k in [-1,0,1]:
                    for l in [-1,0,1]:
                        if m[i+k][j+l]==1:
                            g[(i-1)*w+j-1].append((i+k-1)*w+j+l-1)
    reach = [False]*(w*h)
    def dfs(v):
        reach[v] = True
        for i in g[v]:
            if not reach[i]:
                dfs(i)
    ans = 0   
    for i in range(h*w):
        if g[i] and not reach[i]:
            ans += 1
            dfs(i)

    print(ans)

    w,h = map(int,input().split())