class No697:
    height, width = 0, 0
    cnt = 0

    def __init__(self):
        self.height, self.width = map(int, input().split(" "))
        # 高速化1. 内包表記
        self.water_map = [list(map(int, input().split(" "))) for _ in range(self.height)]

    def solve(self):
        for h in range(self.height):
            for w in range(self.width):
                if self.water_map[h][w] == 1:
                    search_queue = [(h, w)]
                    while len(search_queue) != 0:
                        copy_queue = search_queue.copy()
                        search_queue = list()
                        for py, px in copy_queue:
                            search_dic = [(0, 1, 0, -1), (1, 0, -1, 0)]
                            for i in range(4):
                                vx = px + search_dic[0][i]
                                vy = py + search_dic[1][i]
                                if 0 <= vx < self.width and 0 <= vy < self.height:
                                    if not self.water_map[vy][vx] == 0:
                                        comp = (py + search_dic[1][i], px + search_dic[0][i])
                                        if comp not in search_queue:
                                            search_queue.append((py + search_dic[1][i], px + search_dic[0][i]))
                            self.water_map[py][px] = 0
                    self.cnt += 1
        return self.cnt


if __name__ == "__main__":
    que = No697()
    ans = que.solve()
    print(ans)