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: while True:
    w, h = map(int, input().split())
    if w == 0 and h == 0:
        break
    cnt = 0
    maps = [list(map(int, input().split())) for _ in range(h)]
    for x in range(w):
        for y in range(h):
            if maps[y][x] == 0:
                continue
            else:
                cnt += 1
                maps[y][x] = 0
                stack = [(y, x)]
                while stack:
                    f_y, f_x = stack.pop()
                    for dy in range(-1, 2):
                        for dx in range(-1, 2):
                            t_y = f_y + dy
                            t_x = f_x + dx
                            if 0 <= t_y <= h - 1 and 0 <= t_x <= w - 1 and maps[t_y][t_x] == 1:
                                maps[t_y][t_x] = 0
                                stack.append((t_y, t_x))
    print(cnt)

Python: class UnionSet:
        def __init__(self, nmax):
            self.size = [1]*nmax
            self.id = [i for i in range(nmax+1)]
        def root(self, i):
            while i != self.id[i]:
                self.id[i] = self.id[self.id[i]]
                i = self.id[i]
            return i
        def connected(self, p, q): return self.root(p) == self.root(q)
        def unite(self, p, q):
            i, j = self.root(p), self.root(q)
            if i == j: return
            if self.size[i] < self.size[j]:
                self.id[i] = j
                self.size[j] += self.size[i]
            else:
                self.id[j] = i
                self.size[i] += self.size[j]
    # UNION-FIND library
     
def id(r, c):
        global w
        return r*w+c

mv = [[-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 == 0: break
        arr = [[] for r in range(h)]
        u = UnionSet(w*h)
        for r in range(h): arr[r] = list(map(int, input().split()))
        for r in range(h):
                for c in range(w):
                        if not arr[r][c]: continue
                        for i in range(8):
                                r2, c2 = r + mv[i][0], c + mv[i][1]
                                if r2 < 0 or r2 >= h or c2 < 0 or c2 >= w or not arr[r2][c2]: continue
                                u.unite(id(r, c), id(r2, c2))
        ans = 0
        for r in range(h):
                for c in range(w):
                        if arr[r][c] and u.root(id(r, c)) == id(r, c): ans += 1
        print(ans)

Python: import sys
import itertools
# import numpy as np
import time
import math
 
sys.setrecursionlimit(10 ** 7)
 
from collections import defaultdict
 
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines

while True:
    W, H = map(int, input().split())
    if W == 0 and H == 0:
        break
    W = W + 2
    H = H + 2
    A = [0] * H
    for i in range(H):
        if i == 0 or i == H - 1:
            A[i] = ['#'] * W
        else:
            A[i] = ['#'] + list(map(int, input().split())) + ['#']
    checked = [[False] * W for _ in range(H)]

    def dfs(s):
        dirs = [(1,0),(1,1),(0,1),(-1,1),(-1,0),(-1,-1),(0,-1),(1,-1)]
        x, y = s
        if checked[x][y]:
            return False
        if A[x][y] == 0:
            return False

        checked[x][y] = True
        for d in dirs:
            dx, dy = d
            if A[x + dx][y + dy] == '#':
                continue
            if checked[x + dx][y + dy]:
                continue
            if A[x + dx][y + dy] == 1:
                dfs((x + dx, y + dy))
        return True

    ans = 0
    for i in range(1, H - 1):
        for j in range(1, W - 1):
            if dfs((i, j)):
                ans += 1
    print(ans)

Python: def erase(x, y):
    c[y][x] = '0'
    for dx, dy in ((1, 0), (1, 1), (0, 1), (-1, 1), (-1, 0), (-1, -1), (0, -1), (1, -1)):
        nx, ny = x + dx, y + dy
        if 0 <= nx <= w -1 and 0 <= ny <= h - 1:
            if c[ny][nx] == '1':
                erase(nx, ny)

while True:
    w, h = map(int, input().split())
    c = [[i for i in input().split()] for _ in range(h)]
    ans = 0
    for y in range(h):
        for x in range(w):
            if c[y][x] == '1':
                ans += 1
                erase(x, y)
    print(ans)