69 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			Java
		
	
	
	
	
	
			
		
		
	
	
			69 lines
		
	
	
		
			2.0 KiB
		
	
	
	
		
			Java
		
	
	
	
	
	
| /*
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|  * File: list.java
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|  * Created Time: 2022-11-25
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|  * Author: Krahets (krahets@163.com)
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|  */
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| 
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| package chapter_array_and_linkedlist;
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| 
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| import java.util.*;
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| 
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| public class list {
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|     public static void main(String[] args) {
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|         /* 初始化列表 */
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|         // 注意数组的元素类型是 int[] 的包装类 Integer[]
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|         Integer[] numbers = new Integer[] { 1, 3, 2, 5, 4 };
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|         List<Integer> list = new ArrayList<>(Arrays.asList(numbers));
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|         System.out.println("列表 list = " + list);
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| 
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|         /* 访问元素 */
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|         int num = list.get(1);
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|         System.out.println("访问索引 1 处的元素,得到 num = " + num);
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| 
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|         /* 更新元素 */
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|         list.set(1, 0);
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|         System.out.println("将索引 1 处的元素更新为 0 ,得到 list = " + list);
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| 
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|         /* 清空列表 */
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|         list.clear();
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|         System.out.println("清空列表后 list = " + list);
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| 
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|         /* 尾部添加元素 */
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|         list.add(1);
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|         list.add(3);
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|         list.add(2);
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|         list.add(5);
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|         list.add(4);
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|         System.out.println("添加元素后 list = " + list);
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| 
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|         /* 中间插入元素 */
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|         list.add(3, 6);
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|         System.out.println("在索引 3 处插入数字 6 ,得到 list = " + list);
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| 
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|         /* 删除元素 */
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|         list.remove(3);
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|         System.out.println("删除索引 3 处的元素,得到 list = " + list);
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| 
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|         /* 通过索引遍历列表 */
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|         int count = 0;
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|         for (int i = 0; i < list.size(); i++) {
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|             count++;
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|         }
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| 
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|         /* 直接遍历列表元素 */
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|         count = 0;
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|         for (int n : list) {
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|             count++;
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|         }
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| 
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|         /* 拼接两个列表 */
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|         List<Integer> list1 = new ArrayList<>(Arrays.asList(new Integer[] { 6, 8, 7, 10, 9 }));
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|         list.addAll(list1);
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|         System.out.println("将列表 list1 拼接到 list 之后,得到 list = " + list);
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| 
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|         /* 排序列表 */
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|         Collections.sort(list);
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|         System.out.println("排序列表后 list = " + list);
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|     }
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| }
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