单链表结点删除 C语言实现

#include<stdlib.h>
#include<stdio.h>

#define N 15

typedef struct linklist
{
int data;
struct linklist *next;
}list, *plist;

/*创建链表*/
void create_list(plist* head)
{
int i;
if (NULL == *head)/*若头为空，插入第一个元素1*/
{
plist phead = (plist)malloc(sizeof(list));
phead->data = 1;
phead->next = NULL;
*head = phead;
}
for (i = 2; i < N + 1; i++)/*插入数据2~15*/
{
plist p = (plist)malloc(sizeof(list));
p->data = i;
p->next = *head;
*head = p;
}
}
/*打印输出*/
void print_list(plist head)
{
plist p = head;
while (p != NULL)
{
printf("%d ", p->data);
p = p->next;
}
printf("\n");
}
/*删除结点*/
void delete_node(plist* head, int num)
{
plist elem = *head;
plist temp = NULL;

if (elem->data == num)
{
*head = elem->next;
free(elem);
return;
}
else
{
while (elem != NULL)
{
temp = elem;
elem = elem->next;
if (NULL == elem)
{
printf("\n------------未找到要删除的结点----------------\n\n");
return;
}
else if (elem->data == num)/*找到data值为num的结点*/
{
temp->next = elem->next; /*elem前一个结点的next指向elem元素后一个结点*/
free(elem);/*释放被删除的结点占用的空间*/
break;
}
}
}

}

void main()
{
int num;
plist head;
head = NULL;
create_list(&head);

printf("请输入要删除的结点（1~15）：\n");
scanf("%d", &num);

printf("删除结点之前：\n");
print_list(head);

delete_node(&head, num);
printf("删除结点之后：\n");
print_list(head);

system("pause");
}