用C写了一个带头尾指针的单向链表,仅在尾部进行插入操作,在任意位置进行删除操作。因为只用到这么些功能,又因为懒,所以没有扩展。因为插入是固定在尾部进行,带一个尾指针的好处是显而易见的。当然删除时要付出一些开销。
list.h
-------------------------------------------
/* list.h
** Copyright 2004 Coon Xu.
** Author: Coon Xu
** Date: 06 Sep 2004
*/
#ifndef LIST_H
#define LIST_H
#include <stdio.h>
#include <stdlib.h>
struct listnode
{
struct listnode* next;
int data;
};
struct list
{
struct listnode* head;
struct listnode* tail;
int count;
};
void list_init(struct list*);
void list_insert(struct list*, struct listnode*);
int list_delete(struct list*, struct listnode*);
#endif
------------------------------------------
list.c
------------------------------------------
/* list.c
** Copyright 2004 Coon Xu.
** Author: Coon Xu
** Date: 06 Sep 2004
*/
#include "list.h"
void list_init(struct list* myroot)
{
myroot->count = 0;
myroot->head = NULL;
myroot->tail = NULL;
}
void list_insert(struct list* myroot, struct listnode* mylistnode)
{
myroot->count++;
mylistnode->next = NULL;
if(myroot->head == NULL)
{
myroot->head = mylistnode;
myroot->tail = mylistnode;
}
else
{
myroot->tail->next = mylistnode;
myroot->tail = mylistnode;
}
}
int list_delete(struct list* myroot, struct listnode* mylistnode)
{
struct listnode* p_listnode = myroot->head;
struct listnode* pre_listnode;
//myroot is empty
if(p_listnode == NULL)
{
return 0;
}
if(p_listnode == mylistnode)
{
myroot->count--;
//myroot has only one node
if(myroot->tail == mylistnode)
{
myroot->head = NULL;
myroot->tail = NULL;
}
else
{
myroot->head = p_listnode->next;
}
return 1;
}
while(p_listnode != mylistnode && p_listnode->next != NULL)
{
pre_listnode = p_listnode;
p_listnode = p_listnode->next;
}
if(p_listnode == mylistnode)
{
pre_listnode->next = p_listnode->next;
myroot->count--;
return 1;
}
else
{
return 0;
}
}
-------------------------------------------
main.c
-------------------------------------------
#include <stdio.h>
#include <stdlib.h>
#include "list.h"
int main(int argc, char *argv[])
{
struct list l;
list_init(&l);
int ix = 0;
for(ix = 0; ix < 10; ix++)
{
struct listnode* p_node = malloc(sizeof(struct listnode));
p_node->data = ix;
list_insert(&l, p_node);
}
struct listnode* p_listnode = l.head;
while(p_listnode != NULL)
{
printf("%d\n", p_listnode->data);
p_listnode = p_listnode->next;
}
int input;
printf("input the number you want delete:\n");
scanf("%d", &input);
while(input > 0)
{
p_listnode = l.head;
while(p_listnode->next != NULL && p_listnode->data != input)
{
p_listnode = p_listnode->next;
}
if(p_listnode->data == input)
{
printf("Delete success!!\nprint the list!!\n");
list_delete(&l, p_listnode);
free(p_listnode);
p_listnode = l.head;
while(p_listnode != NULL)
{
printf("%d\n", p_listnode->data);
p_listnode = p_listnode->next;
}
}
else
{
printf("not find %d\n", input);
}
scanf("%d", &input);
}
system("PAUSE");
return 0;
}