数据结构 --- 循环队列（队列的顺序存储结构）

工程目录结构图:

common.h:

 1 //#ifndef __common_h__
 2 //#define __common_h__
 3
 4 #define OK 1
 5 #define ERROR 0
 6 #define TRUE 1
 7 #define FALSE 0
 8
 9 #define MAXSIZE 20
10
11 typedef int Status;        //函数的返回结果，OK、ERREO、TRUE、FALSE
12 typedef int ElemType;   //结点数据域的数据类型
13
14 //#endif

common.h:

1 #include "common.h"
2
3 Status visit(ElemType e)
4 {
5     printf("%d , ", e);
6     return OK;
7 }

Queue.h:

1 //循环队列的结构
2 typedef struct
3 {
4     ElemType data[MAXSIZE];
5     int front;                //头指针
6     int rear;                //尾指针，队列不为空，指向队列尾元素的下一位
7 }SqQueue;

Queue.c:

 1 #include <stdio.h>
 2 #include "common.h"
 3 #include "Queue.h"
 4
 5 Status InitQueue(SqQueue *Q)
 6 {
 7     Q->front = 0;
 8     Q->rear = 0;
 9     return OK;
10 }
11
12 Status ClearQueue(SqQueue *Q)
13 {
14     Q->front = Q->rear = 0;
15     return OK;
16 }
17
18 Status QueueEmpty(SqQueue Q)
19 {
20     if (Q.front == Q.rear)
21         return OK;
22     else
23         return FALSE;
24 }
25
26 int GetQueueLength(SqQueue Q)
27 {
28     return (Q.rear - Q.front + MAXSIZE) % MAXSIZE;
29 }
30
31 Status EnQueue(SqQueue *Q, ElemType e)
32 {
33     //队列已满
34     if ((Q->rear + 1) % MAXSIZE == Q->front)
35         return FALSE;
36
37     Q->data[Q->rear] = e;
38     Q->rear = (Q->rear + 1) % MAXSIZE; //队尾向后以一个元素，队满后则转移到队列头部
39     return OK;
40 }
41
42 Status DeQueue(SqQueue *Q, ElemType *e)
43 {
44     if (Q->front == Q->rear)   //队列为空
45         return FALSE;
46
47     *e = Q->data[Q->front];
48     Q->front = (Q->front + 1) % MAXSIZE;
49
50     return OK;
51 }
52
53 Status GetQueueHead(SqQueue *Q, ElemType *e)
54 {
55     if (Q->front == Q->rear) //队列为空
56         return FALSE;
57     *e = Q->data[Q->front];
58     return OK;
59 }
60
61 Status QueueTraverse(SqQueue Q)
62 {
63     int index = Q.front;
64     while ((index + Q.front) != Q.rear)  //遍历完成
65     {
66         visit(Q.data[index]);
67         index = (index + 1) % MAXSIZE;
68     }
69
70     return OK;
71 }
72
73 void StartQueue()
74 {
75     SqQueue Q;
76     if (OK == InitQueue(&Q))
77         printf("\n循环队列初始化成功!\n");
78
79     for (int i = 1; i <= 10; ++i)
80         EnQueue(&Q, i * 2);
81
82     printf("\n\n插入数据1-10后的队列长度为: %d\n", GetQueueLength(Q));
83
84     printf("\n\n队列中的元素是:\n");
85     QueueTraverse(Q);
86
87     int e;
88     DeQueue(&Q, &e);
89     printf("\n\n队首出列: %d\n", e);
90     printf("\n\n队首出列后的队列长度为: %d\n", GetQueueLength(Q));
91
92     GetQueueHead(&Q, &e);
93     printf("\n\n队首元素为: %d\n", e);
94
95     ClearQueue(&Q);
96     printf("\n\n清空后的队列长度: %d\n", GetQueueLength(Q));
97 }

main.c:

1 int main()
2 {
3     //LinkListStart();
4     //StackStart();
5     //LinkStackStart();
6     StartQueue();
7     getchar();
8     return 0;
9 }

原文地址：https://www.cnblogs.com/luguoshuai/p/9256360.html