如何在java中获取二维数组列表的max/min

List<List<Integer>> arrayLists = new ArrayList<>();
arrayLists.add(Arrays.asList(1, 2, 3));
arrayLists.add(Arrays.asList(4, 5, 6));
arrayLists.add(Arrays.asList(7, 8, 9));

int max = Integer.MIN_VALUE;
int min = Integer.MAX_VALUE;

for (List<Integer> list : arrayLists) {
    for (int num : list) {
        if (num > max) {
            max = num;
        }
        if (num < min) {
            min = num;
        }
    }
}

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public class Main {
    public static void main(String[] args) {
        List<List<Integer>> arrayLists = new ArrayList<>();
        arrayLists.add(Arrays.asList(1, 2, 3));
        arrayLists.add(Arrays.asList(4, 5, 6));
        arrayLists.add(Arrays.asList(7, 8, 9));

        int max = Integer.MIN_VALUE;
        int min = Integer.MAX_VALUE;

        for (List<Integer> list : arrayLists) {
            for (int num : list) {
                if (num > max) {
                    max = num;
                }
                if (num < min) {
                    min = num;
                }
            }
        }

        System.out.println("最大值：" + max);
        System.out.println("最小值：" + min);
    }
}