线性表—由链表实现

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

typedef int datatype;

typedef struct _node_
{
 datatype data;
 struct _node_ *next;
} linknode, *linklist;

linklist CreateEmptyLinklist_1()
{
 linklist h;

 h = (linklist)malloc(sizeof(linknode));
 h->next = NULL;

 return h;
}

void CreateEmptyLinklist_2(linklist *h)
{
 *h = (linklist)malloc(sizeof(linknode));
 (*h)->next = NULL;

 return;
}

int LengthLinklist(linklist h)
{
 int length = 0;

 h = h->next;
 while (h != NULL)
 {
  length++;
  h = h->next;
 }

 return length;
}

int EmptyLinklist(linklist h)
{
 return (NULL == h->next);
}

void VisitLinklist(linklist h)
{
 h = h->next;

 while  (h != NULL)
 {
  printf("%d ", h->data);
  h = h->next;
 }

 return;
}

int LocateLinklist(linklist h, datatype x)
{
 int pos = 0;

 h = h->next;
 while (h != NULL)
 {
  if (h->data == x) return pos;
  pos++;
  h = h->next;
 }

 return -1;
}

int InsertLinklist_1(linklist h, datatype x, int pos)
{
 linklist p;

 if ((pos < 0) || (pos > LengthLinklist(h))) return -1;

 while ( pos-- ) h = h->next;
 p = (linklist)malloc(sizeof(linknode));
 p->data = x;
 p->next = h->next;
 h->next = p;

 return;
}

void InsertLinklist_2(linklist h, datatype x)
{
 linklist p = h, q;

 q = (linklist)malloc(sizeof(linknode));
 q->data = x;

 while ((p->next != NULL) && (p->next->data < x)) p = p->next;
 q->next = p->next;
 p->next = q;

 return;
}

int DeleteLinklist_1(linklist h, int pos)
{
 linklist q;

 if ((pos < 0) || (pos >= LengthLinklist(h))) return -1;

 while ( pos-- ) h = h->next;
 q = h->next;
 h->next = q->next;
 free(q);

 return 0;
}

void DeleteLinklist_2(linklist h, datatype x)
{
 linklist q = h->next;

 while (NULL != q)
 {
  if (q->data == x)
  {
   h->next = q->next;
   free(q);
  }
  else
  {
   h = q;
  }
  q = h->next;
 }

 return;
}

void ClearLinklist(linklist h)
{
 linklist p = h->next, q;

 while (p != NULL)
 {
  q = p;
  p = p->next;
  free(q);
 }

 h->next = NULL;

 return;
}

int main()
{
 int i;
 linklist h, p, q;

 h = CreateEmptyLinklist_1();
 //CreateEmptyLinklist_2(&h);
 p = h;
 for (i=0; i<10; i++)
 {
  q = (linklist)malloc(sizeof(linknode));
  q->data = i;
  q->next = NULL;
  p->next = q;
  p = q;
 }
 
 p = h->next;
 while (p != NULL)
 {
  printf("%d " ,p->data);
  p = p->next;
 }
 printf("\n");

 return 0;
}