链栈的构建—数据结构算法

#include <stdio.h>
#include <stdlib.h>
typedef struct List
{
int data;
struct List *next;
}list,*p_list;

void creat_list(list **p)
{	
int item;
list *temp;
list *target;
printf("输入节点的值，输入0结束\n");
while(1)
{
scanf("%d",&item);
if(item==0)return;

if(*p==NULL) 
{
*p=(list *)malloc(sizeof(list));
if(!*p)exit(0);
(*p)->data=item;
(*p)->next=*p;
}
else	
{
for(target=*p;target->next!=*p;target=target->next);

temp=(list *)malloc(sizeof(list));
if(!temp)exit(0);
temp->data=item;
temp->next=*p; 
target->next=temp;
}
}
}
void insert(list **pNode,int place,int num) 
{
list *temp,*target;
int i;
if(place==1)	
{	
temp=(list *)malloc(sizeof(list));
if(!temp)exit(0);
temp->data=num;
for(target=*pNode;target->next!=*pNode;target=target->next);

temp->next=*pNode;
target->next=temp;
*pNode=temp;
}

else	
{	
for(i=1,target=*pNode;target->next!=*pNode&&i!=place-1;target=target->next,i++);
temp=(list *)malloc(sizeof(list));
temp->data=num;

temp->next=target->next;
target->next=temp;
}

}

void Delete(list **pNode,int place) 
{
list *temp,*target;
int i;
temp=*pNode;
if(temp==NULL)	
{
printf("这是一个空指针 无法删除\n");
return;
}
if(place==1)	
{	
for(target=*pNode;target->next!=*pNode;target=target->next);
temp=*pNode;

*pNode=(*pNode)->next;
target->next=*pNode;
free(temp);
}
else
{	
for(i=1,target=*pNode;target->next!=*pNode&&i!=place-1;target=target->next,i++); 
if(target->next==*pNode)	
{
for(target=*pNode;target->next->next!=*pNode;target=target->next);
temp=target->next;	
target->next=*pNode;
printf("数字太大删除尾巴\n");
free(temp);
}
else
{
temp=target->next;
target->next=temp->next;
free(temp);
}
}
}

int findval(list *pNode,int val) 
{
int i=1;
list *node;
node=pNode;
while(node->data!=val&&node->next!=pNode)
{
i++;
node=node->next;
}
if(node->next==pNode&&node->data!=val)
{
return -1;
}
return i;
}



void show(list *p)
{
list *temp;
temp=p;
do
{
printf("%5d",temp->data);
temp=temp->next;	
}
while(temp!=p);

printf("\n");
}