//给出队接口的定义,然后基于List接口及其实现类给出队的两种实现类(采用ArrayList和LinkkedList //实现分别给出队的实现类)

 1 //给出队接口的定义,然后基于List接口及其实现类给出队的两种实现类(采用ArrayList和LinkkedList
 2 //实现分别给出队的实现类)
 3 package classwork9;
 4 
 5 public interface Dui {
 6     public abstract void push();
 7     public abstract void pop();
 8 }
 9 package classwork9;
10 
11 import java.util.ArrayList;
12 import java.util.List;
13 import java.util.Scanner;
14 
15 public class Duiarray implements Dui {
16 
17     List<Double> a=new ArrayList<Double>();
18     Scanner in=new Scanner(System.in);
19     @Override
20     public void push() {
21         System.out.println("请输入入队元素:");
22         double x=in.nextDouble();
23         a.add(x);
24     }
25 
26     @Override
27     public void pop() {
28         System.out.println("出队元素为:"+a.get(0));
29         a.remove(0);
30 
31     }
32 
33 }
34 package classwork9;
35 
36 public class DuiarrayTest {
37     public static void main(String[] args) {
38         Duiarray a=new Duiarray();
39         a.push();
40         a.push();
41         a.push();
42         a.pop();
43         a.pop();
44     }
45 }
46 package classwork9;
47 
48 import java.util.LinkedList;
49 import java.util.List;
50 import java.util.Scanner;
51 
52 public class Duilink implements Dui {
53 
54      List<Integer> a=new LinkedList<Integer>();
55         Scanner in=new Scanner(System.in);
56         @Override
57         public void push() {
58             System.out.println("请输入入队元素:");
59             int x=in.nextInt();
60             ((LinkedList<Integer>) a).addFirst(x);
61         }
62 
63         @Override
64         public void pop() {
65             System.out.println("出队元素为:"+((LinkedList<Integer>) a).getLast());
66             ((LinkedList<Integer>) a).removeLast();
67 
68         }
69 
70 }
71 package classwork9;
72 
73 public class DuilinkTest {
74 
75     public static void main(String[] args) {
76         Duilink a=new Duilink();
77         a.push();
78         a.push();
79         a.push();
80         a.pop();
81         a.pop();
82     }
83 
84 }