数据结构(7) - 顺序队列
作者：互联网
顺序队列是队列的顺序存储结构，顺序队列实际上是运算受限的顺序表。和顺序表一样，顺序队列用一个向量空间来存放当前队列中的元素。由于队列的队头和队尾的位置是变化的，设置两个指针front和rear分别指示队头元素和队尾元素在向量空间中的位置，它们的初值在队列初始化时均应设置为0。
sequence-queue.c
1 /**
2 * C data structure sequence queue example.
3 *
4 * License - MIT.
5 */
6
7 #include "sequence-queue.h"
8
9
10 /**
11 * sequeue_isempty - Determine if the queue is empty.
12 */
13 bool sequeue_isempty(LPSEQUEUE lpqueue)
14 {
15 return (lpqueue->front == lpqueue->rear);
16 }
17
18
19 /**
20 * sequeue_isfull - Determine if the queue is full.
21 */
22 bool sequeue_isfull(LPSEQUEUE lpqueue)
23 {
24 return (lpqueue->front == (lpqueue->rear + 1) % MAX_DATA_SIZE);
25 }
26
27
28 /**
29 * sequeue_put - Put data to queue.
30 */
31 int sequeue_put(LPSEQUEUE lpqueue, int data)
32 {
33 /* Determine if sequential stack is full. */
34 if (sequeue_isfull(lpqueue))
35 return -1;
36
37 /* Put data to stack. */
38 lpqueue->rear = (lpqueue->rear + 1) % MAX_DATA_SIZE;
39 lpqueue->data[lpqueue->rear] = data;
40
41 return 0;
42 }
43
44
45 /**
46 * sequeue_get - Get data from queue.
47 */
48 int sequeue_get(LPSEQUEUE lpqueue, int *data)
49 {
50 /* Determine if sequential stack is empty. */
51 if (sequeue_isempty(lpqueue))
52 return -1;
53
54 /* Get data from stack. */
55 lpqueue->front = (lpqueue->front + 1) % MAX_DATA_SIZE;
56 *data = lpqueue->data[lpqueue->front];
57
58 return 0;
59 }
60
61
62 /**
63 * sequeue_init - Initialize sequence queue.
64 */
65 int sequeue_init(LPSEQUEUE *lpqueue)
66 {
67 /* Allocate memory space. */
68 *lpqueue = (LPSEQUEUE) malloc(sizeof(SEQUEUE));
69
70 if (NULL == *lpqueue) {
71 printf("Error in queue init.\n");
72 return -1;
73 }
74
75 (*lpqueue)->front = MAX_DATA_SIZE - 1;
76 (*lpqueue)->rear = MAX_DATA_SIZE - 1;
77
78 return 0;
79 }
80
81
82 /**
83 * sequeue_clear - Clear sequence queue.
84 */
85 int sequeue_clear(LPSEQUEUE lpqueue)
86 {
87 int tmp = -1;
88
89 while (!sequeue_isempty(lpqueue))
90 {
91 sequeue_get(lpqueue, &tmp);
92 }
93
94 free(lpqueue);
95 lpqueue = NULL;
96
97 return 0;
98 }
sequence-queue.h
1 /**
2 * C data structure sequence queue example.
3 *
4 * License - MIT.
5 */
6
7 #ifndef __SEQUENCE_QUEUE_H__
8 #define __SEQUENCE_QUEUE_H__
9
10
11 #include <stdio.h>
12 #include <stdlib.h>
13 #include <stdbool.h>
14
15 #define MAX_DATA_SIZE 10
16
17 typedef struct _SEQUEUE {
18 int data[MAX_DATA_SIZE];
19 int front, rear;
20 } SEQUEUE, *LPSEQUEUE;
21
22
23 bool sequeue_isempty (LPSEQUEUE lpqueue);
24 bool sequeue_isfull (LPSEQUEUE lpqueue);
25 int sequeue_put (LPSEQUEUE lpqueue, int data);
26 int sequeue_get (LPSEQUEUE lpqueue, int *data);
27 int sequeue_init (LPSEQUEUE *lpqueue);
28 int sequeue_clear (LPSEQUEUE lpqueue);
29
30
31 #endif /* __SEQUENCE_QUEUE_H__ */
main.c
1 /**
2 * C data structure sequence queue example.
3 *
4 * License - MIT.
5 */
6
7 #include <stdio.h>
8
9 #include "sequence-queue.h"
10
11
12 /**
13 * queue_test - Use queue test example.
14 */
15 int queue_test(LPSEQUEUE lpqueue, int buf[], int len)
16 {
17 int i = 0;
18 int data = 0;
19
20 printf("Put data: ");
21
22 for (i = 0; i < len; i++) {
23 sequeue_put(lpqueue, buf[i]);
24 printf("%d ", buf[i]);
25 }
26
27 printf("\nGet data: ");
28
29 for (i = 0; i < len; i++) {
30 sequeue_get(lpqueue, &data);
31 printf("%d ", data);
32 }
33
34 printf("\n");
35
36 return 0;
37 }
38
39
40 /**
41 * Main function.
42 */
43 int main(void)
44 {
45 int buf[5] = {1, 2, 3, 4, 5};
46 LPSEQUEUE sequeue = NULL;
47
48 sequeue_init(&sequeue);
49
50 queue_test(sequeue, buf, 5);
51
52 sequeue_clear(sequeue);
53
54 return 0;
55 }
Makefile
1 # Makefile 2 CC = gcc 3 CFLAGS = -Wall -g -O0 4 5 SRC = main.c sequence-queue.c 6 7 OBJ = sequeue-test 8 9 $(OBJ) : $(SRC) 10 $(CC) $(CFLAGS) -o $@ $^ 11 12 clean: 13 $(RM) $(OBJ) *.o *.*.sw?
详细请参考Github: [Link] [https://github.com/Phoebus-Ma/C-Helper/tree/main/Class-1/Queue.C].
标签：顺序,LPSEQUEUE,lpqueue,队列,queue,int,数据结构,data,sequeue 来源： https://www.cnblogs.com/tinyshark/p/16411768.html