单向链表简单实现

/*********************************************************************************
*      Copyright:  (C) 2015 songyong<handy_skyoutlook.com>
*                  All rights reserved.
*
*       Filename:  link.c
*    Description:  This file
*
*        Version:  1.0.0(2015年09月11日)
*         Author:  sky <handy_sky@outlook.com>
*      ChangeLog:  1, Release initial version on "2015年09月11日 21时35分16秒"
*
********************************************************************************/
#include<stdio.h>
#include<stdlib.h>

#define LEN sizeof(struct link)

typedef struct link{
int             data;
struct link    *next;
}node;
node *create(node *head)
{
node  *p1, *p2;
int n =0;

p1 = p2 =(node *)malloc(LEN);
printf("请输入一个数据:");
scanf("%d",&p1->data);

while(p1->data != 0)
{
n++;
if(1 == n)
{
head = p1;
}
else
{
p2->next=p1;
}
p2 = p1;
p1= (node *)malloc(LEN);
printf("请输入数据,输入0终止:\n");
scanf("%d",&p1->data);
}
p2->next = NULL;
return (head);
}

/********************************************************************************
*  Description:
*   Input Args:
*  Output Args:
* Return Value:
********************************************************************************/
int main (int argc, char **argv)
{
node *create(node *head);
void print(node *head);
node *Reverse(node *head);
node *sort(node *head);
node *getlink(node *head, int i);
void deletlink(node *head);
node *insertlink(node *head);//尾插

node *head =NULL;
node *p =NULL;
int          i=0;

head = create(head);
printf("链表逆置前的数据:\n");
print(head);

head = Reverse(head);
printf("链表逆置后的数据:\n");
print(head);

printf("链表从小到大: \n");
sort(head);
print(head);

printf("请输入现在您想要打印的节点序号:\n");
scanf("%d",&i);
p =getlink(head,i);
printf("node:%d\n",p->data);

head = insertlink(head);//尾插
print(head);

deletlink(head);
print(head);

return 0;
} /* ----- End of main() ----- */

void print(node *head)
{
node *temp;
temp = head;

if(NULL == head)
return;
while(temp != NULL)
{
printf(" %d",temp->data);
temp = temp->next;
}
printf("\n");
}

#if 0
node *creatlist(void)
{
int val,i,n;
node *p,*q,*head;

head = NULL;
printf("please input link mount..\n");
scanf("%d", &n);
for(i =0;i < n; i++)
{
printf("please input link:\n");
scanf("%d",val);
q = p = (node *)malloc(sizeof(node));
p->data = val;
if(NULL == head)
{
q = head = p;
}
else {
q->next = p;
q = p;
}
}
p->next = NULL;
return 0;
}
#endif

node *Reverse(node *head)
{
node *p, *q, *r;
p = head;
q = r =NULL;

if(NULL == head)
return;
while(p)//link not empty
{
q = p->next;
p->next = r;
r = p;
p = q;
}
return r;
}

node *sort(node *head)
{
node *f,*s;
int temp;
f = head;

for(;f != NULL; f = f->next)
{
for(s = f->next; s != NULL; s = s->next)
{
if(f->data > s->data)
{
temp = f->data;
f->data = s->data;
s->data = temp;
}
}
}
return head;
}

node * getlink(node *head, int n)
{
node *p = head;
int j = 1;

if(0 == n)
return head;
if(0 > n)
return NULL;

while(p && j<n)
{
p = p->next;
j++;
}
return p;
}

void deletlink(node *head)
{
int i;
node *p,*q;

printf("请输入你要删除的节点序号:(输入0可跳过)\n");
scanf("%d",&i);

while(1)
{
if(0 == i)
return;

p = getlink(head,i);

if( NULL == p->next )
{
q = getlink(head, i-1);
q->next = NULL;
free(p);
}
else
{
q = p->next;
p->data = p->next->data;//这里删除采用的是将后一个节点的值传给前一个节点，再释放后一个节点。
p->next = q->next;
free(q);
}

printf("请输入你要删除的节点序号:(输入0可跳过)\n");
scanf("%d",&i);
}
}

node *insertlink(node *head)//尾插 i > 0
{
int i=0;
node *p, *s;

s = (node *)malloc(LEN);
printf("请输入新节点数据:\n");
scanf("%d",&i);
s->data = i;
printf("请输入你要插入位置:\n");
scanf("%d",&i);
while(i == 1)
{
s->next =head;
head = s;
return head;
}
#if 1
p = getlink(head,i-1);
s->next = p->next;
p->next = s;
return head;
#endif

}