java数据结构----队列，优先级队列

1 package com.cn.queue;
 2 /**
 3  * 数据结构之队列实现
 4  * @author Administrator
 5  *
 6  */
 7 public class Queue {
 8 private int maxsize;
 9 private long[] queuearray;
10 private int front;
11 private int rear;
12 private int nItems;
13 public Queue(int s){
14     maxsize = s;
15     queuearray = new long[maxsize];
16     front = 0;  ---删除后记录当前的坐标
17     rear = -1;  ---插入后记录当前的坐标
18     nItems = 0; ---当前队列中有的元素计数
19 }
20 public void insert(long j){
21     if (rear == maxsize - 1)  ---满了之后又循环赋值
22         rear = -1;
23     queuearray[++ rear] = j;
24     nItems ++;
25 }
26 public long remove(){
27     long temp = queuearray[front ++];
28     if (front == maxsize)  ---空了之后又循环赋值
29         front = 0;
30     nItems --;
31     return temp;
32 }
33 public long peekFront(){
34     return queuearray[front];
35 }
36 public boolean isEmpty(){
37     return (nItems == 0);
38 }
39 public boolean isFull(){
40     return (nItems == maxsize);
41 }
42 public int size(){
43     return nItems;
44 }
45 
46 }

1 package com.cn.queue;
 2 
 3 public class QueueTest {
 4 public static void main(String[] args) {
 5     Queue q = new Queue(100);
 6     q.insert(100);
 7     q.insert(200);
 8     q.insert(300);
 9     while (q.size()!=0){
10         System.out.print(q.remove()+"   ");
11     }
12     System.out.println("");
13     System.out.println(q.isEmpty());
14 }
15 }

1 package com.cn.queue;
 2 /**
 3  * 优先级队列的实现代码
 4  * @author Administrator
 5  *
 6  */
 7 public class PriorityQ {
 8 private int maxsize;
 9 private long[] queuearray;
10 private int nItems;
11 public PriorityQ(int s){
12     maxsize = s;
13     queuearray = new long[maxsize];
14     nItems = 0;
15 }
16 public void insert(long item){
17     int k;
18     if (nItems == 0)
19         queuearray[nItems ++] = item;
20     else{
21         for(k = nItems - 1;k >= 0;k --){
22             if (item > queuearray[k])
23                 queuearray[k + 1] = queuearray[k];
24             else
25                 break;
26         }
27         queuearray[k + 1] = item;
28         nItems ++;
29     }
30 }
31 public long remove(){
32     return queuearray[-- nItems];
33 }
34 public long peekmin(){
35     return queuearray[nItems - 1];
36 }
37 public boolean isEmpty(){
38     return (nItems == 0);
39 }
40 public boolean isFull(){
41     return (nItems == maxsize);
42 }
43 }