抱歉,你查看的文章不存在

Max Area of Island

Given a non-empty 2D array grid of 0's and 1's, an island is a group of 1's (representing land) connected 4-directionally (horizontal or vertical.) You may assume all four edges of the grid are surrounded by water.

Find the maximum area of an island in the given 2D array. (If there is no island, the maximum area is 0.)

Example 1:

[[0,0,1,0,0,0,0,1,0,0,0,0,0],
 [0,0,0,0,0,0,0,1,1,1,0,0,0],
 [0,1,1,0,1,0,0,0,0,0,0,0,0],
 [0,1,0,0,1,1,0,0,1,0,1,0,0],
 [0,1,0,0,1,1,0,0,1,1,1,0,0],
 [0,0,0,0,0,0,0,0,0,0,1,0,0],
 [0,0,0,0,0,0,0,1,1,1,0,0,0],
 [0,0,0,0,0,0,0,1,1,0,0,0,0]]

Given the above grid, return

6

. Note the answer is not 11, because the island must be connected 4-directionally.

Example 2:

[[0,0,0,0,0,0,0,0]]

Given the above grid, return 0.

Note: The length of each dimension in the given grid does not exceed 50.

class Solution {
    public int maxAreaOfIsland(int[][] grid) {
        int max = 0;
        for (int i = 0; i < grid.length; i++) {
            int[] js = grid[i];
            for (int j = 0; j < js.length; j++) {
                max = Math.max(max, island(grid, i, j));
            }
        }
        return max;
    }
    
    private static int island(int[][] grid,int x,int y){
        if(x<0 || x>=grid.length || y<0 || y>=grid[x].length){
            return 0;
        }
        int area = 0;
        if(grid[x][y] == 1){
            area=1;
        }else{
            return 0;
        }
        grid[x][y] = 0;
        area += island(grid, x, y-1)+island(grid, x-1, y)+island(grid, x, y+1)+island(grid, x+1, y);
        return area;
    }
}

本文参与腾讯云自媒体分享计划,欢迎正在阅读的你也加入,一起分享。

编辑于

luozhiyun的源码解析

47 篇文章16 人订阅

扫码关注云+社区

领取腾讯云代金券