hello-algo/codes/java/chapter_array_and_linkedlist/list.java
Yudong Jin e720aa2d24
feat: Revised the book (#978)
* Sync recent changes to the revised Word.

* Revised the preface chapter

* Revised the introduction chapter

* Revised the computation complexity chapter

* Revised the chapter data structure

* Revised the chapter array and linked list

* Revised the chapter stack and queue

* Revised the chapter hashing

* Revised the chapter tree

* Revised the chapter heap

* Revised the chapter graph

* Revised the chapter searching

* Reivised the sorting chapter

* Revised the divide and conquer chapter

* Revised the chapter backtacking

* Revised the DP chapter

* Revised the greedy chapter

* Revised the appendix chapter

* Revised the preface chapter doubly

* Revised the figures
2023-12-02 06:21:34 +08:00

66 lines
2 KiB
Java

/**
* File: list.java
* Created Time: 2022-11-25
* Author: Krahets (krahets@163.com)
*/
package chapter_array_and_linkedlist;
import java.util.*;
public class list {
public static void main(String[] args) {
/* 初始化列表 */
// 注意数组的元素类型是 int[] 的包装类 Integer[]
Integer[] numbers = new Integer[] { 1, 3, 2, 5, 4 };
List<Integer> nums = new ArrayList<>(Arrays.asList(numbers));
System.out.println("列表 nums = " + nums);
/* 访问元素 */
int num = nums.get(1);
System.out.println("访问索引 1 处的元素,得到 num = " + num);
/* 更新元素 */
nums.set(1, 0);
System.out.println("将索引 1 处的元素更新为 0 ,得到 nums = " + nums);
/* 清空列表 */
nums.clear();
System.out.println("清空列表后 nums = " + nums);
/* 在尾部添加元素 */
nums.add(1);
nums.add(3);
nums.add(2);
nums.add(5);
nums.add(4);
System.out.println("添加元素后 nums = " + nums);
/* 在中间插入元素 */
nums.add(3, 6);
System.out.println("在索引 3 处插入数字 6 ,得到 nums = " + nums);
/* 删除元素 */
nums.remove(3);
System.out.println("删除索引 3 处的元素,得到 nums = " + nums);
/* 通过索引遍历列表 */
int count = 0;
for (int i = 0; i < nums.size(); i++) {
count += nums.get(i);
}
/* 直接遍历列表元素 */
for (int x : nums) {
count += x;
}
/* 拼接两个列表 */
List<Integer> nums1 = new ArrayList<>(Arrays.asList(new Integer[] { 6, 8, 7, 10, 9 }));
nums.addAll(nums1);
System.out.println("将列表 nums1 拼接到 nums 之后,得到 nums = " + nums);
/* 排序列表 */
Collections.sort(nums);
System.out.println("排序列表后 nums = " + nums);
}
}