题解 | #岛屿的最大面积#

dfs,遍历矩阵找到值为 1 并进行搜索;

#
# 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
#
# 
# @param grid int整型二维数组 
# @return int整型
#
class Solution:
    def maxAreaIsland(self , grid: List[List[int]]) -> int:
        # write code here
        if not grid:
            return 0
        m, n = len(grid), len(grid[0])
        dirs = [(-1, 0), (0, 1), (1, 0), (0, -1)]
        def dfs(x, y, grid):
            grid[x][y] = 0
            res = 1
            for i, j in dirs:
                xi, yi = x + i, y + j
                if 0 <= xi < m and 0 <= yi < n and grid[xi][yi] == 1:
                    res += dfs(xi, yi, grid)
            return res
        res = 0
        for i in range(m):
            for j in range(n):
                if grid[i][j] == 1:
                    res = max(res, dfs(i, j, grid))
        return res