无难度 按照题意解题即可
按照遍历顺序只需判断左边和上边是否相连
class Solution:
def countBattleships(self, board):
"""
:type board: List[List[str]]
:rtype: int
"""
m=len(board)
if m==0: return 0
n=len(board[0])
count=0
for i in range(m):
for j in range(n):
if board[i][j]=='X':
if (i-1<0 or board[i-1][j]=='.') and (j-1<0 or board[i][j-1]=='.'):
count+=1
return count