from collections import deque

class Solution:
  def countClosedIslands(self, matrix):
    countClosedIslands = 0
    
    self.n = len(matrix)
    self.m = len(matrix[0])

    self.matrix = matrix

    self.visited = [[False for y in range(self.m)] for x in range(self.n)]

    for i in range(self.n):
      for j in range(self.m):
        if self.matrix[i][j] == 1 and not self.visited[i][j]:
          is_closed = self.bfs(i, j)
          if is_closed:
            countClosedIslands += 1

    return countClosedIslands

  def bfs(self, p, q):
    queue = deque([(p, q)])

    closed = True

    while queue:
      row, col = queue.popleft()

      if row < 0 or row >= self.n or col < 0 or col >= self.m:
        closed = False
        continue

      if self.matrix[row][col] == 0:
        continue

      if not self.visited[row][col]:
        queue.append((row - 1, col))
        queue.append((row, col - 1))
        queue.append((row + 1, col))
        queue.append((row, col + 1))

        self.visited[row][col] = True

    return closed