1 #include <stdio.h>
  2 #include <stdlib.h>
  3 
  4 #define MAX_DATA_SIZE           10
  5 
  6 typedef struct _SEQLIST {
  7     int data[MAX_DATA_SIZE];
  8     int last_index;
  9 } SEQLIST, *LPSEQLIST;
 10 
 11 /**
 12  * seqlist_isempty - Determine if the table is empty.
 13 */
 14 int seqlist_isempty(LPSEQLIST lplist)
 15 {
 16     return (-1 == lplist->last_index);
 17 }
 18 
 19 /**
 20  * seqlist_isfull - Determine if the table is full up.
 21 */
 22 int seqlist_isfull(LPSEQLIST lplist)
 23 {
 24     return ((MAX_DATA_SIZE - 1) == lplist->last_index);
 25 }
 26 
 27 /**
 28  * seqlist_insert - Add the specified data  by index.
 29 */
 30 int seqlist_insert(LPSEQLIST lplist, int index, int data)
 31 {
 32     int i;
 33 
 34     if ((index < 0) || (index > MAX_DATA_SIZE - 1)) {
 35         printf("invalid index!\n");
 36         return -1;
 37     }
 38 
 39     /* Move the data behind the index. */
 40     for (i = lplist->last_index; i >= index; i--)
 41         lplist->data[i + 1] = lplist->data[i];
 42 
 43     /* Insert the data. */
 44     lplist->data[index] = data;
 45 
 46     /* Update the last index. */
 47     lplist->last_index++;
 48 
 49     return 0;
 50 }
 51 
 52 /**
 53  * seqlist_del - Deletes the specified data by index.
 54 */
 55 int seqlist_del(LPSEQLIST lplist, int index)
 56 {
 57     int i;
 58 
 59     if ((index < 0) || (index > MAX_DATA_SIZE - 1)) {
 60         printf("invalid index!\n");
 61         return -1;
 62     }
 63 
 64     /* Move the data behind the index forward. */
 65     for (i = index; i < lplist->last_index; i++)
 66         lplist->data[i] = lplist->data[i + 1];
 67 
 68     /* Update the last index. */
 69     lplist->last_index--;
 70 
 71     return 0;
 72 }
 73 
 74 /**
 75  * seqlist_init - Initialize sequence list.
 76 */
 77 int seqlist_init(LPSEQLIST *lpHead)
 78 {
 79     /* Allocate memory space. */
 80     *lpHead = (LPSEQLIST)malloc(sizeof(SEQLIST));
 81     if (NULL == *lpHead) {
 82         perror("malloc");
 83         exit(1);
 84     }
 85 
 86     (*lpHead)->last_index = -1;
 87 
 88     return 0;
 89 }
 90 
 91 /**
 92  * seqlist_exit - clear sequence list.
 93 */
 94 int seqlist_exit(LPSEQLIST lpHead)
 95 {
 96     int i = -1;
 97 
 98     if (seqlist_isempty(lpHead)) {
 99         for (i = 0; i < lpHead->last_index; i++)
100             seqlist_del(lpHead, i);
101     }
102 
103     free(lpHead);
104     lpHead = NULL;
105 
106     return 0;
107 }
108 
109 void test_show(LPSEQLIST lplist)
110 {
111     int i;
112 
113     for (i = 0; i <= lplist->last_index; i++)
114         printf("%d ", lplist->data[i]);
115 
116     printf("\n");
117 }
118 
119 int main(void)
120 {
121     int i = -1;
122 
123     LPSEQLIST lphead;
124 
125     seqlist_init(&lphead);
126 
127     for (i = 0; i < MAX_DATA_SIZE; i++)
128         seqlist_insert(lphead, i, i + 1);
129 
130     test_show(lphead);
131 
132     seqlist_del(lphead, 3);
133 
134     test_show(lphead);
135 
136     seqlist_exit(lphead);
137 
138     return 0;
139 }