题解 | #岛屿数量#

dfs，走过的标0

#
# 判断岛屿数量
# @param grid char字符型二维数组 
# @return int整型
#
class Solution:
    def solve(self , grid ):
        # write code here
        m = len(grid)
        if m == 0:
            return 0
        n = len(grid[0])
        if n == 0:
            return 0
        def dfs(i, j):
            if i < 0 or i >= len(grid) or j < 0 or j >= len(grid[0]):
                return 0
            if grid[i][j] == '0':
                return 0

            grid[i][j] = '0'
            up_i, up_j = i-1, j
            dfs(i-1, j)
            dfs(i+1, j)
            dfs(i, j-1)
            dfs(i, j+1)
            return 1


        def display():
            for i in grid:
                print(i)
        res = 0
        for i in range(m):
            for j in range(n):

                res += dfs(i, j)
#                 print(i, j)
#                 display()
        return res