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: 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)