Go: package main

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

const (
	initialBufSize = 100000
	maxBufSize     = 1000000
)

var sc *bufio.Scanner

func initScanner(r io.Reader) *bufio.Scanner {
	buf := make([]byte, initialBufSize)

	sc := bufio.NewScanner(r)
	sc.Buffer(buf, maxBufSize)
	sc.Split(bufio.ScanWords) // bufio.ScanLines
	return sc
}

func main() {
	sc = initScanner(os.Stdin)
	resolve()
}

func resolve() {
	results := []int{}
	for true {
		w, h := scanInt(sc), scanInt(sc)
		if w == 0 && h == 0 {
			break
		}
		grid := make([][]int, h)
		for i := 0; i < h; i++ {
			grid[i] = make([]int, w)
			for j := 0; j < w; j++ {
				grid[i][j] = scanInt(sc)
			}
		}
		num := 0
		for i := range loop0(h) {
			for j := range loop0(w) {
				start := pos{y: i, x: j}
				if grid[start.y][start.x] == 0 {
					continue
				}
				num++
				_dfs(grid, w, h, start)
			}
		}
		results = append(results, num)
	}
	for _, v := range results {
		fmt.Println(v)
	}
	return
}

func _dfs(grid [][]int, w, h int, start pos) {
	grid[start.y][start.x] = 0
	for _, df := range []pos{
		pos{1, 0}, pos{-1, 0},
		pos{0, -1}, pos{0, 1},
		pos{1, 1}, pos{-1, -1},
		pos{-1, 1}, pos{1, -1},
	} {
		np := addPos(start, df)
		if np.y < 0 || h <= np.y || np.x < 0 || w <= np.x {
			continue
		}
		if grid[np.y][np.x] == 0 {
			continue
		}
		_dfs(grid, w, h, np)
	}
}

type pos struct{ x, y int }

func addPos(p, d pos) pos {
	return pos{
		x: p.x + d.x,
		y: p.y + d.y,
	}
}

func loop0(n int) chan int {
	return loop(0, n-1, 1)
}

func loop1(n int) chan int {
	return loop(1, n, 1)
}

func loop(s, e, d int) chan int {
	ch := make(chan int)
	go func() {
		for i := s; i <= e; i += d {
			ch <- i
		}
		close(ch)
	}()
	return ch
}

// snip-scan-funcs
func scanInt(sc *bufio.Scanner) int {
	sc.Scan()
	i, _ := strconv.Atoi(sc.Text())
	return int(i)
}
func scanString(sc *bufio.Scanner) string {
	sc.Scan()
	return sc.Text()
}

Python: move = [[0, 1], [0, -1], [-1, 0], [1, 0], [1, 1], [1, -1], [-1, -1], [-1, 1]]
from collections import deque
def main(w, h):
    c = [list(map(int, input().split())) for i in range(h)]
    ans = 0
    for y in range(h):
        for x in range(w):
            if c[y][x]:
                ans += 1
                q = deque()
                q.append((x, y))
                while q:
                    xx, yy = q.popleft()
                    for mx, my in move:
                        xm = xx + mx
                        ym = yy + my
                        if 0 <= xm < w and 0 <= ym < h:
                            if c[ym][xm]:
                                c[ym][xm] = 0
                                q.append((xm,ym))
    print(ans)


while 1:
    w, h = map(int, input().split())
    if w == h == 0:
        break
    main(w,h)

Python: import sys

# 再帰の深さの上限変更
sys.setrecursionlimit(10**4)

def DFS(v,visit):
  visit[v] = True
  for u in adj[v]:
    if visit[u] == False:
      DFS(u,visit)

while(1):
  W, H = map(int, input().split())
  if (W,H) == (0,0):# 入力終了
    sys.exit()
  
  C = []
  for _ in range(H):
    tmp = list(map(int, input().split()))
    C.append(tmp)

  # 縦横斜め8方向が島か探索し、隣接リストを作成する
  dx = [1,-1,0,0,1,-1,-1,1]
  dy = [0,0,1,-1,1,1,-1,-1]
  
  # 隣接リスト
  adj = [[] for i in range(H*W)]
  
  for i in range(H):
    for j in range(W):
      if C[i][j] == 1:# 陸である
        # 周りが陸か探索する
        tmp = []
        for k in range(8):
          x,y = j+dx[k], i+dy[k]
          if 0 <= y < H and 0 <= x < W:
            if C[y][x] == 1:
              tmp.append(W*y + x)
        adj[W*i+j] = tmp
  # print(adj)
        
  # 深さ優先探索を行う
  # 訪問チェック
  visit = [False for i in range(H*W)]
  
  ans = 0
  for i in range(H):
    for j in range(W):
      if C[i][j] == 1 and visit[W*i+j] == False:
        DFS(W*i+j,visit)
        ans += 1
  print(ans)

Python: from queue import Queue

def dfs(x,y,c):
    que = Queue()
    que.put((x, y))

    while not que.empty():
        x, y = que.get()
        if c[x][y] == 0:
            continue

        c[x][y] = 0
        for dx in range(-1, 2):
            for dy in range(-1, 2):
                sx, sy = x + dx, y + dy
                if sx < 0 or sx >= h or sy < 0 or sy >= w:
                    continue
                que.put((sx, sy))
    return c

while True:
    w,h = map(int,input().split())
    if w == h == 0:
        break
    wh = w * h
    c = [list(map(int,input().split())) for _ in range(h)]
    ans = 0
    for x in range(h):
        for y in range(w):
            if c[x][y] == 0:
                continue
            ans += 1
            c = dfs(x,y,c)
    print(ans)

Python: import sys
from pprint import pprint


class UnionFind:
    def __init__(self):
        self._parent = {}
        self._rank = {}
        self._equiv = {}
    
    def _find(self, x):
        if self._parent[x] == x:
            return self._parent[x]
        else:
            p = self._find(self._parent[x])
            self._parent[x] = p
            return p
    
    def _set_parent(self, child, parent):
        self._parent[child] = parent
        self._equiv[parent].update(self._equiv.pop(child))
    
    def _union(self, x, y):
        x = self._find(x)
        y = self._find(y)
        if x == y: return
        if self._rank[x] > self._rank[y]:
            self._set_parent(y, x)
        elif  self._rank[x] < self._rank[y]:
            self._set_parent(x, y)
        else:
            self._set_parent(x, y)
            self._rank[x] += 1
    
    def _make_set(self, x):
        self._parent[x] = x
        self._rank[x] = 0
        self._equiv[x] = {x}
    
    def unite(self, *elements):
        if not elements: return
        for x in elements:
            if x in self._parent: continue
            self._make_set(x)
        x0 = elements[0]
        for x in elements[1:]:
            self._union(x0, x)
    
    def groups(self):
        return [set(e) for e in self._equiv.values()]


def pairs(ncol, nrow):
    # ?????????
    for x in range(ncol - 1):
        for y in range(nrow):
            yield [(x, y), (x + 1, y)]

    # ?????????
    for x in range(ncol):
        for y in range(nrow - 1):
            yield [(x, y), (x, y + 1)]

    # ???????????????
    for x in range(ncol - 1):
        for y in range(nrow - 1):
            yield [(x, y), (x + 1, y + 1)]

    # ???????????????
    for x in range(ncol - 1):
        for y in range(1, nrow):
            yield [(x, y), (x + 1, y - 1)]


def solve(ncol, nrow, rows):
 
    f = UnionFind()
    for x in range(ncol):
        for y in range(nrow):
            if rows[y][x]:
                f.unite((x, y))
    for (x1, y1), (x2, y2) in pairs(ncol, nrow):
        if rows[y1][x1] and rows[y2][x2]:
            f.unite((x1, y1), (x2, y2))
    return len(f.groups())


def main():
    while True:
        ncol, nrow = map(int, input().split())
        if ncol == 0 and nrow == 0:
            break
        rows = []
        for _ in range(nrow):
            row = list(map(int, input().split()))
            rows.append(row)
        print(solve(ncol, nrow, rows))

main()

Python: # -*- coding: utf-8 -*-


def search(n, m, tile, N, M):
    for dy, dx in zip([-1, -1, -1, 0, 0, 1, 1, 1], [-1, 0, 1, -1, 1, -1, 0, 1]):
        if 0 <= dy + n < N and 0 <= dx + m < M:
            if tile[dy + n][dx + m] == '1':
                tile[dy + n][dx + m] = '2'
                search(dy + n, dx + m, tile, N, M)


while True:
    M, N = map(int, input().split())
    if M == 0 and N == 0:
        break
    tile = [input().split() for n in range(N)]
    ans = 0
    for n in range(N):
        for m in range(M):
            if tile[n][m] == '1':
                tile[n][m] = '2'
                search(n, m, tile, N, M)
                ans += 1
    print(ans)