class Solution(object):

     def __init__(self):

         self.cons = 0

         self.S = list()

     def dfs(self,m,n,v,A):

         while len(self.S) > 0:

             cur = self.S.pop(-1)

             cur_x = cur[0]

             cur_y = cur[1]

             v[cur_x][cur_y] =  1

             self.cons += 1

             if cur_x > 0 and A[cur_x-1][cur_y]==1 and v[cur_x-1][cur_y] == 0:

                 self.S.append([cur_x-1,cur_y])

                 self.dfs(m,n,v,A)

             if cur_x < m - 1 and A[cur_x + 1][cur_y]==1 and v[cur_x + 1][cur_y]== 0:

                 self.S.append([cur_x+1,cur_y])

                 self.dfs(m,n,v,A)

             if cur_y > 0 and A[cur_x][cur_y-1]==1 and v[cur_x][cur_y-1]==0:

                 self.S.append([cur_x,cur_y-1])

                 self.dfs(m,n,v,A)

             if cur_y < n - 1 and A[cur_x][cur_y+1]==1 and v[cur_x][cur_y+1]==0:

                 self.S.append([cur_x,cur_y+1])

                 self.dfs(m,n,v,A)

         return 0

     def numEnclaves(self, A: 'List[List[int]]') -> int:

         row = len(A)

         coloum = len(A[0])

         visited =  [[0 for c in range(coloum)] for r in range(row)]

         sumsA = 0

         for i in range(row):

             for j in range(coloum):

                 sumsA += A[i][j]

         if sumsA == 0:

             return 0

         #first row and last row

         for i in [0,row-1]:

             for j in range(coloum):

                 if A[i][j] == 0 or visited[i][j] == 1:

                     continue

                 else:

                     self.S.append([i,j])

                     self.dfs(row,coloum,visited,A)

         #first coloum and last coloum

         for j in [0,coloum - 1]:

             for i in range(row):

                 if A[i][j] == 0 or visited[i][j] == 1:

                     continue

                 else:

                     self.S.append([i,j])

                     self.dfs(row,coloum,visited,A)

         return sumsA - self.cons