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: import sys

sys.setrecursionlimit(10 ** 4)

w = h = 0
islands = []


def dfs(ii: int, jj: int) -> None:
    global islands
    islands[jj][ii] = 0

    for i in range(ii - 1, ii + 2):
        for j in range(jj - 1, jj + 2):
            if 0 <= i < w and 0 <= j < h and islands[j][i] > 0:
                dfs(i, j)


def main() -> None:
    ans = []
    global islands, w, h
    while True:
        cnt = 0
        w, h = map(int, input().split())
        if w + h == 0:
            break
        islands = [list(map(int, input().split())) for _ in range(h)]
        for j in range(h):
            for i in range(w):
                if islands[j][i] > 0:
                    cnt += 1
                    dfs(i, j)
        ans += [cnt]
    print("\n".join(map(str, ans)))


if __name__ == "__main__":
    main()

Python: import sys
sys.setrecursionlimit(10000)


def integrate(x, i, j):
    if x[i-1][j-1] != 1 and x[i-1][j] != 1 and x[i-1][j+1] != 1 \
        and x[i][j-1] != 1 and x[i][j+1] != 1 and x[i+1][j-1] != 1 \
            and x[i+1][j] != 1 and x[i+1][j+1] != 1:
            return 0
    if x[i-1][j] == 1:
        x[i-1][j] = 0
        integrate(x, i-1, j)
    if x[i-1][j-1] == 1:
        x[i-1][j-1] = 0
        integrate(x, i-1, j-1)
    if x[i+1][j] == 1:
        x[i+1][j] = 0
        integrate(x, i+1, j)
    if x[i+1][j+1] == 1:
        x[i+1][j+1] = 0
        integrate(x, i+1, j+1)
    if x[i][j-1] == 1:
        x[i][j-1] = 0
        integrate(x, i, j-1)
    if x[i+1][j-1] == 1:
        x[i+1][j-1] = 0
        integrate(x, i+1, j-1)
    if x[i][j+1] == 1:
        x[i][j+1] = 0
        integrate(x, i, j+1)
    if x[i-1][j+1] == 1:
        x[i-1][j+1] = 0
        integrate(x, i-1, j+1)
    return 0


answer = []

while True:
    w, h = map(int, input().split())
    if w == 0 and h == 0:
        break
    c = [[] for i in range(h+2)]
    c[0] = [2 for i in range(w+2)]

    for i in range(1, h+1):
        c[i].append(2)
        c_i = list(map(int, input().split()))
        c[i].extend(c_i)
        c[i].append(2)

    c[h+1] = [2 for i in range(w+2)]

    count = 0

    for i in range(1, h+1):
        for j in range(1, w+1):
            if c[i][j] == 1:
                c[i][j] = 0
                integrate(c, i, j)
                count += 1

    answer.append(count)

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

Python: import sys
from collections import deque

sys.setrecursionlimit(10 ** 7)
input = sys.stdin.readline
f_inf = float('inf')
mod = 10 ** 9 + 7


def resolve():
    ans = []
    while True:
        W, H = map(int, input().split())
        if W == H == 0:
            break
        grid = [list(map(int, input().split())) for _ in range(H)]

        res = 0
        visited = [[False] * W for _ in range(H)]
        for y in range(H):
            for x in range(W):
                if grid[y][x] == 1 and not visited[y][x]:
                    res += 1
                    que = deque([[y, x]])
                    while que:
                        h, w = que.pop()
                        for dh, dw in ((1, 0), (-1, 0), (0, 1), (0, -1), (1, 1), (1, -1), (-1, 1), (-1, -1)):
                            next_h, next_w = h + dh, w + dw
                            if next_h < 0 or next_h >= H or next_w < 0 or next_w >= W or grid[next_h][next_w] == 0:
                                continue
                            else:
                                if not visited[next_h][next_w]:
                                    visited[next_h][next_w] = True
                                    que.append([next_h, next_w])
        ans.append(res)
    print(*ans, sep="\n")


if __name__ == '__main__':
    resolve()

Python: w, h = map(int,input().split())
c = [list(map(int,input().split())) for j in range(h)]
count = 0

def dfs(x,y):
    c[x][y] = 0
    for dx in [-1,0,1]:
        for dy in [-1,0,1]:
            nx = x + dx
            ny = y + dy
            if(0 <= nx < w and 0 <= ny <= h and c[nx][ny] == 1 ):
                dfs(nx, ny)
    
for i in range(h):
    for j in range(w):
        if (c[i][j] == 1):
            dfs(i,j)
            count += 1

print(count)

Python: from collections import deque
while True:
    w, h = map(int, input().split())
    if w == 0 and h == 0:
        break
    areas = [list(map(int, input().split())) for _ in range(h)]

    # print(areas)

    # 島の数を出す。
    # 島の定義は陸地続きであること。ただし、斜めもみて、陸だったらそれは島
    # 左上からスタートして、陸続きのものは飛ばす

    move_positions = [[-1, -1], [-1, 0], [-1, 1],
                      [0, -1], [0, 1], [1, -1], [1, 0], [1, 1]]
    count = 0
    queue = deque([])
    for i in range(h):
        for j in range(w):
            start_position = [i, j]
            queue.append(start_position)
            has_island = False
            while queue:
                now_position = queue.popleft()
                if areas[now_position[0]][now_position[1]] == 0:
                    continue
                has_island = True
                areas[now_position[0]][now_position[1]] = 0
                for move_position in move_positions:
                    next_position = [now_position[0] + move_position[0],
                                     now_position[1] + move_position[1]]
                    if 0 <= next_position[0] and next_position[0] < h and 0 <= next_position[1] and next_position[1] < w:
                        queue.append(next_position)
            if has_island:
                count += 1
    print(count)