leetcode——16.19.水域大小

public int[] pondSizes(int[][] land) {
        List<Integer> list = new ArrayList<>();
        int temp;
        for (int i = 0; i < land.length; i++) {
            for (int j = 0; j < land[0].length; j++) {
                temp = findpond(land, i, j);
                if (temp != 0) {
                    list.add(temp);
                }
            }
        }
        int[] result = list.stream().mapToInt(Integer::valueOf).toArray();
        Arrays.sort(result);
        return result;
    }

    private int findpond(int[][] land, int i, int j) {
        int sum = 0;
        if (i < 0 || i >= land.length || j < 0 || j >= land[0].length || land[i][j] != 0) {
            return sum;
        }
        land[i][j] = -1;
        sum++;
        sum += findpond(land, i + 1, j);
        sum += findpond(land, i, j + 1);
        sum += findpond(land, i - 1, j);
        sum += findpond(land, i, j - 1);
        sum += findpond(land, i + 1, j + 1);
        sum += findpond(land, i - 1, j - 1);
        sum += findpond(land, i + 1, j - 1);
        sum += findpond(land, i - 1, j + 1);
        return sum;
    }