1.png

    1. class Solution {
    2.     public int maxAreaOfIsland(int[][] grid) {
    3.         int ans = 0;
    4.         for (int i = 0; i != grid.length; ++i) {
    5.             for (int j = 0; j != grid[0].length; ++j) {
    6.                 int cur = 0;
    7.                 Queue<Integer> queuei = new LinkedList<Integer>();
    8.                 Queue<Integer> queuej = new LinkedList<Integer>();
    9.                 queuei.offer(i);
    10.                 queuej.offer(j);
    11.                 while (!queuei.isEmpty()) {
    12.                     int cur_i = queuei.poll(), cur_j = queuej.poll();
    13.                     if (cur_i < 0 || cur_j < 0 || cur_i == grid.length || cur_j == grid[0].length || grid[cur_i][cur_j] != 1) {
    14.                         continue;
    15.                     }
    16.                     ++cur;
    17.                     grid[cur_i][cur_j] = 0;
    18.                     int[] di = {0, 0, 1, -1};
    19.                     int[] dj = {1, -1, 0, 0};
    20.                     for (int index = 0; index != 4; ++index) {
    21.                         int next_i = cur_i + di[index], next_j = cur_j + dj[index];
    22.                         queuei.offer(next_i);
    23.                         queuej.offer(next_j);
    24.                     }
    25.                 }
    26.                 ans = Math.max(ans, cur);
    27.             }
    28.         }
    29.         return ans;
    30.     }
    31. }

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